# Ideas for practical post-apocalyptic currency 100 years from now

First, let me introduce the setting.

It's happening in post-apocalyptic SE Europe (Balkans specifically), about 100 years from now. Strange genetic disease wiped out large portion of humanity in a matter of a few years. The rest of humanity killed and pillaged each other until our numbers were indeed few. The surviving humans have a genetic disorder which makes pregnancy harder.

Nature is, for an unknown reason to people, thriving, mutating, being more hostile to people. Wild plants are growing slightly faster, predators are bigger, stronger, smarter and more dangerous. Beside that there are the "wild ones", feral humans that live like animals. All this has made trade and traveling quite hard, but not impossible.

Cities are overgrown, forests are bigger.

People are living in smaller independent settlements (100-300 people), scattered, fortified. Bandits and roamers are common. Settlements are somewhat self sustaining, but still need to trade between each other - for example some are agricultural, having extra veggies but lacking meat and tools, others are hunting or fishing based, and there is one specific settlement, based around the old University, which harbors and preserves "old" technology and knowledge, and uses that knowledge as a commodity. There is no unified government or force, and all attempts do do such have failed.

Technology is somewhat preserved, but only partially. For example, people know what solar panels are, or that somehow electricity can be produced from a windmill, but only a very few people actually know how it works and the science behind it.

Now, finally, to the QUESTION.

I am looking for a form of currency that people can use in trade or for paying for services. I don't need a fiat currency as modern money, or backed up currency like bottlecaps from Fallout series (they are backed by water). I need something that has actual practical use and value to people.

I've researched that various things have been used as currency before, like animal pelts, cattle, shells. But, I can't really picture post apocalyptic random traveler hauling bunch of pelts with him or dragging 3 cows and 2 pigs just to have a way to pay anything anywhere. Or how do you pay for shelter in a settlement or pay your bodyguard for a week of protection? Give him two chickens and he's on his way?

People will also say why don't they just barter, but, in a bartering system you can't really pay for someone's services (protecting, fixing, and so on).

I think in this setting, also, precious metals like gold and silver are practically useless for surviving, except they are rare and look pretty.

So, I welcome ideas for currency that fits in this:

• Has actual practical use and value to people in this environment
• Should be rare, hard to find, but not impossible.
• Hard to counterfeit or cheat with
• Size matters - should be easily transportable (like precious metal coins or lumps, only, as stated above, they don't really fit the bill, that you can carry it easily)
• Durability, can't be fragile
• Take in consideration described technological level and society, and that a hundred years have passed since "the end" and most things are gone and decayed

I've been trying to come up with a realistic solution to this problem but having hard time. Any help or ideas would be most welcome.

/I think in this setting, also, precious metals like gold and silver are practically useless for surviving, except they are rare and look pretty./

That has always been true of gold and silver. Also, they are durable and not easy to fake.

If there are people, there will be people who want to let others know they are rich, and gold can accomplish that. Gold ornaments display your wealth and at the same time look pretty. Beautiful, durable things can be made of gold. Many ancient economies were predicated on the trade of luxury goods and gifts between powerful people - gold is always acceptable in this role.

There is gold now, and the gold now will be around in 100 years. Your people will have access to gold artifacts collected from the ruins even if they cannot mine it.

• @Bora Lots of tribal societies picked something that was pretty as a type of currency. Certain types of seashells could be found throughout Pre-contact North America, as jewelry and currency. Most tribes had a general idea of how many shells would get a piece of clothing, food, weapons, skins, etc. Gold and Silver was used exactly the same way between clans, tribes and villages in Europe before they had a real government system. en.wikipedia.org/wiki/Shell_money#North_America – Dan Clarke Mar 9 '18 at 2:55
• @Bora: You've got a bunch of people trading with each other, and that's all the organization you need. You should also have a lot of pre-existing gold & silver coins, and a niche for people to go explore ruins for more of them, or other valuable stuff. – jamesqf Mar 9 '18 at 4:23
• Gold also has the advantage of being mostly useless. You do not want, as currency material, a commodity whose demand might suddenly increase, so that a lot of it gets repurposed, suddenly leaving you with a shortage of cash, otherwise known as a depression – nzaman Mar 9 '18 at 7:18
• @nzaman Gold is quite useful. It doesn't rust or tarnish. It's quite useful for false teeth because of that. It's also why its used as a coating for electrical connectors. Silver is useful for its antimicrobial effects. – Samuel Mar 9 '18 at 18:14
• It's not the answer OP wants, but it's the answer OP needs. Gold and silver have been used as currency since time immemorial, even when circumstances were a lot harsher than what is described, and they are going to keep on trucking into the future whether you like it or not. – guenthmonstr Mar 10 '18 at 1:28

All this has made trade and traveling quite hard, but not impossible.

Then People are living in smaller independent settlements (100-300 people), scattered, fortified. Bandits and roamers are common. Settlements are somewhat self sustaining, but still need to trade between each other - for example some are agricultural, having extra veggies but lacking meat and tools, others are hunting or fishing based,

You're set against precious metals, so barter is all that's left.

Yes, but, gold, silver, they, as an exotic goods, a currency, are always connected with organized societies, be it bronze age society, antiquity or modern age... This is not the case anymore.

Society was organized, and there was gold and silver. Lots of it. Have them go scavenge it.

and there is one specific settlement, based around the old University, which harbors and preserves "old" technology and knowledge, and uses that knowledge as a commodity.

Knowledge is not a commodity, though what it can produce is.

• There's always stratification in society, even in 100 person villages. – RonJohn Mar 9 '18 at 13:33
• "how is that "fair" and how would it even out?" That confuses the hell out of me. A poor settlement with a large stash of gold trades what it has (the gold, a little at a time) for what it needs. That's basic commerce. ISTM that you need a basic course in economics. – RonJohn Mar 9 '18 at 15:16
• English is my second language and i might've wrongly expressed myself. The problem im thinking about is, that we say that gold/silver becomes a currency, a medium of exchange, what if someone shows up. a group that found a way in central bank, found tons of gold and silver stashed there, that would put that group, in wealth, above the others, which may be richer in a real sense (resources, skills). This would bring such an inflation that it would probably crash the whole system of that currency. – Bora Mar 9 '18 at 16:17
• Copper, lead, iron, gold, silver. And everything in Henry Taylor's excellent answer. The very fact that that stuff is only made in limited quantities makes it valuable. – RonJohn Mar 9 '18 at 17:32
• @Bora This happened to 17th century Span when they were extracting gold and silver from their new American colonies - the influx caused significant inflation and domestic industry become moribund compared to other nations. If a village discovers a supply of a valuable durable good, they gain great wealth by trading it with others. Unless your scenario includes some god overseeing the world to ensure everything remains "fair", then any sense of fairness is irrelevant - life isn't fair - but at the point of making up gods to intervene to ensure fairness, you can just make up anything. – pluckedkiwi Mar 9 '18 at 19:18

In some respects, this problem has already been solved in an environment that simulates your post-apocalyptic environment; Prison. The problem that you face is that your 'currency' has to be durable. Everything you own will be useful in this kind of environment as you can't afford to keep things around that don't have some practical value. It's the durability part that is more of a problem.

In prisons all over the world, things like tinned fish have been used as currency for a very long time. It bypasses the actual cash limits imposed upon prisoners, is relatively light-weight and easy to transfer, can be controlled in terms of the amount that enters the system, and most importantly of all, lasts long enough that it can be traded many times before consumed.

Let's assume for a moment that your settlements have some way of preserving their food goods. Let us further assume that there is a food type that is more or less ubiquitous, preservable, and preferably not so tasty; say a food of last resort. For the purposes of this example, let's call it Dried Brussel Sprouts (DBS).

These could easily become a centralised currency. If they're everywhere and can be grown at a consistent level of effort by all settlements (say 2 man days of effort per DBS) then it becomes a useful measuring stick of all production. Sure they're edible, but people prefer other foods to DBSs so they only get consumed if you absolutely have to. That means people are willing to trade them and the consistent production effort means that they have a consistent value across settlements.

In the tinned fish example, durability is similar to coins meaning that the currency is easily controlled but in this case, your DBS may only have a trading life of (say) 2 months. After that, it has to be eaten or thrown away. But, you have new DBSs being produced constantly to replace them. Controlled introduction and disposal will be a problem, and as such your DBS based currency is going to be subject to more volatile inflationary and deflationary pressures than a conventional metal-based commodity currency and certainly more than a fiat one, but you're in a post-apocalyptic world; currency fluctuations are seriously the least of your problems.

This would however solve your social welfare initiative issues. In this environment, you could literally throw money at the problem (the starving poor) and know that the help has gone where it's needed.

### SALT!

• Has actual practical use and value to people. Think of the need to preserve food and bodily need for sodium.
• Is hard to counterfeit or cheat with. What can you add to salt to increase it's volume that could be created cheaply in a society like you described? Can't think of none.
• Is easily transportable and not fragile
• Is a a natural resource, so no need for advanced technology to extract it (Romans already extracted and used it a lot)

The single aspect that it does not pass is rarity, since oceans are full of it, but depending on how common are human gatherings (cities) near oceans, it should be somewhat rare.

The outstanding aspect of salt is that it is a low-tech mean to preserve food and everyone needs food during the whole year and not only when the food is available. That has value on its own and should make salt a really sought after product in your post-apocalyptic scenario, just like it was in history where salt was used as a currency.

• If you think salt isn't fragile, try leaving it out in the rain. That said, not a bad answer. – guenthmonstr Mar 10 '18 at 1:22
• @guenthmonstr Thanks man. Good thing about salt's fragility is that if you mix salt with water inside a container, salt can be extracted using a pre-historic tech known as open pan making. DISCLAIMER : I don't add salt to my own food, I just like it's usefulness. – gmauch Mar 12 '18 at 20:57

The most useful direction to take is to look at proto-currency. Something portable enough to carry around, yet useful enough that a community can use it without necessarily having a trader come by for a long time.

Lumps of metal would be most useful for this. Little bits of workable iron or tin, weighed and shaped into ad-hoc coinage and valuable to any community for a wide variety of uses. Iron is useful because you can shape it into nails, tools, weapons, anything you need. Tin similarly because it can be mixed with copper to make similarly useful bronze, or used to patch holes in cookware, make utensils, and so on.

Both are broadly useful for different reasons and a traveller could be fairly sure that they could get a meal and a bunk in exchange for a few lumps of tin or iron. Someone can always find a use for a little extra tin or iron at hand, after all.

If electricity is available to your societies, copper will itself become a potentially useful currency - the stuff is expensive to use even today: one of the advantages of fibre is even that it doesn't need so much copper! And they're going to need a relatively steady stream of the stuff to replace old, worn out cables and extend the network and build generators and all kinds of things so there's never going to be enough.

In future someone may begin minting coins of guaranteed weight this way and continue progress along the historic development of currency, but for your world proto-currency seems more than sufficient.

Outside of workable common metals (which have value over scrap because they're already refined) there's also one precious metal in particular that meets both your rarity and post-apocalyptic value criteria: Platinum.

Platinum is rare. Very rare. The world mining throughput of platinum is about 200 tonnes per annum. (Contrast, Gold sits around 2500 tonnes p.a.) It's also very durable: Scratching platinum only displaces the metal, rather than scraping it off. It's more durable than gold. Platinum recycling is big business, it's so valuable.

It's also valuable. Very valuable. Besides consumer uses like the catalytic converters in cars, platinum is important for a wide variety of applications, such as electronics manufacture, fuel production, medicine, and the very highest temperature applications. Nevermind that not all of these applications would be possible 100 years after the collapse, if nothing else the University would understand how important it is to all kinds of old-world tech they're trying to hold on to and maintain.

This makes platinum a bad currency. It's rare enough as it is, and in the post apocalypse, the University would probably try to have people killed to get hold of it. It's too valuable.

But, there's a way out. Platinum isn't just incredibly valuable - it's incredibly difficult and expensive to refine. Or recycle, for that matter. Most of the actual platinum (from, say, salvaged cars or other platinum-containing scrap) won't be usable, or at least not contain enough to justify the post-apocalyptic cost of making them usable. In divided communities of less than a thousand the infrastructure necessary to do platinum recycling would be near-impossible; University might have a small scale operation but even that would only be able to handle so much at a time.

Which leads to the currency - Platinum Scrap. Platinum-containing scrap is assessed (through a combination of tools and plain old knowhow) for how much platinum might be salvageable from it, and the density of it. More platinum-dense scrap is worth more than the same amount in a lower-grade collection of scrap, because it's closer to being usable (even if still impractical to actually recycle).

Sufficiently high-grade (ie. platinum-dense) scrap would be especially valuable as currency, because high-tech groups like University will happily trade valuable knowledge and equipment for it. Lower grade scrap would be less valuable, but savvy dealers would have an interest in trying to process low grade scrap into higher grade scrap to improve their value. Or, for that matter, selling to people trying to get into the 'rebuilding technology' game for themselves.

Surrounding this particular standard is the possibility of adding Rare-Earth elements keyed to the platinum-scrap standard, all of which have valuable high-tech applications but are useless to most factions due to the lack of viable infrastructure to effectively extract and utilise them.

As with other precious metals, though, platinum-containing scrap isn't directly useful for survival. If it's being utilised at all in your setting it's likely only for research purposes and maintaining whatever technology survivors have been lucky enough to discover and hold on to for 100 years. Most of its value here comes from the demand from those few factions in a position to actually make use of it

• iron, in this environment, is very easy to find, and would have really really low value... even after a hundred years, and rusting and decay, you would have tons of it. Been thinking maybe about some metals or supstances used in some specific technological processes that are mandatory for energy and survival of people (solar panels, batteries for energy storage and so on), but my knowledge in it is really limited... – Bora Mar 9 '18 at 2:39
• @Bora The tricky bit with higher tech goods is that they're even more fragile than ammunition. They'd be rare commodities more than currency, and a slice of a battery is positively useless so they're indivisible. That said, if electrical energy is in play, copper is an excellent potential currency- you'd be surprised how pricey it gets even today. One of the most valuable factors of optical fibre is that you don't need to use so much expensive copper. – Pingcode Mar 9 '18 at 2:50
• Thank you for an idea. So, beside copper, do you have any idea which other metals, that are rare, would be really precious, in society with this technological level? – Bora Mar 9 '18 at 16:09
• @Bora Iron is common, but if you press into a shape then its hard to forge. Look at the nickel,dime,quarter, and etc they have very specific shapes and thicknesses and that makes them harder to forge. You would have minting molds which would be heavily guarded, and only those molds would produce valid currency. Sure I could forge quarters, but the effort it takes exceeds the expected value of 25 cents. Only mints setup to mass produce them would be cost effective. – cybernard Mar 9 '18 at 16:59
• @cybernard That is merely a fiat currency - the value is purely in it being currency for the sake of currency, with no intrinsic value to the coin. – pluckedkiwi Mar 9 '18 at 18:47

The problem here is that you are looking for one currency. And that you are looking for currency.

With the society you describe, there is little pressure towards it. There is almost no trade beyond the community level, and the existing trade will be mostly local.

At community level you actually don't need much currency; rural communities in "developed" countries like England and France in the 16th, 16th and 18th centuries would seldom use money except for "imported goods" and taxes (and a part of taxes would be in locally produced goods). You remember who took three cabbages from you yesterday, so you go today to his house and ask for half a chicken. Playing the system (failing to pay debts, for example, or claiming debts that don't exist) is very hard in small, closed communities.

Additionally, such small communities won't have much to trade. Survival will take most of their efforts, and whatever surplus they can get is probably not very different from town to town.

Historically currency1 developed because:

• A way of certifying the quality of the bullion in the currency.

• A show of sovereignty; the first thing new kings (and claimants to the throne) would do was to mint money with their name/likeness.

Lacking a strong authority able to back it2, there are many hurdles to any proposal. In some areas your proposal may be so abundant as to be meaningless, in others too scarce. If there are big differences between areas (as your example of a tribe settling in Fort Knox) the people in worse off areas may refuse it (why give the effort of a year of work for what, to someone else, is just getting into the vault and getting an ingot?3).

With that said, an unified currency is not a necessity. You may have different currencies in different areas, with some interchange rates that are variable depending of the situation.

A significant alternative for local trade could be credit based in an honor system; if a trader went to town 1 to sell A but there was nothing interesting to him there, a person of authority there could buy A in exchange of a letter (or simply a verbal agreement!) so the trader could go to town 2 and get B from another local authority (who could then ask payment in whatever town 1 could offer).

And, last but not least, the need of survival would make a currency based system very dangerous. So you have a good harvest and get your boxes filled to the rim with (let's say) floppy disks. Good, you are the top dog of your village. But next year there is a drought and everybody harvests are poor. Since floppy disks are not edible, nobody gives you a single carrot for all of your savings. Since there is no honor/community system protecting, you are left to starve.

Now, in the town next door, they do not use currency but they store the food surplus. When the surplus is extra (you have your stores full with last year harvest, and this year harvest is near and will be plentiful) you may exchange some of it for other goods. If the harvest is bad, you just eat your savings.

1 Please be aware that I am talking about currency and not about bullion (e.g. raw slumps of gold and silver).

2 And that needs currency in order to manage their taxes and budgets, because it is the only significant group of people working to grow their own food.

3 And now you are thinking "But the people in Fort Knox may keep it a secret". Well, no, because they will begin using their gold instead of farming/producing goods and people around will know that there is something fishy, even if nobody talks about the vault.

### Barter

People will also say why don't they just barter, but, in a bartering system you can't really pay for someone's services (protecting, fixing, and so on).

Protection was traditionally purchased with goods. The local lord's men would come by and remind you how they protected you. When they left, they would take a bunch of your goods. They would call this taxation.

Similarly, one would pay a doctor or even a lawyer with food (see Harper Lee's To Kill a Mockingbird for a relatively modern example). Food (and for a traveler, a place to stay) would be a common payment for labor. Until they can industrialize, food production will consume most of the time for everyone. It will be relatively scarce. That's why our grandparents were often smaller than us. They weren't fed as well as children.

Paying in jewelry is also an option. It won't work in the first few years after the apocalypse, but a century later? It will be common for jewelry to be traded.

Really advanced economies might coin money (stamped precious metal discs) or even use paper money. Respected money will be used outside its natural environment.

### Prison

I don't know that prison would be a good model here. Part of the problem in prisons is that they don't let the prisoners have actual money. Instead the commissary manages balances. Pretty much the only things they can trade are things that can be bought in the commissary. This includes cigarettes traditionally, as well as canned food. The better something stores, the better money it makes. But it also needs to be desirable and a little scarce.

Canned tuna makes sense in a prison where it may be consumed frequently to add to one's diet and where one can store it. Post apocalypse, they can't can things and even if they could, it would weigh too much. The traveler would eat it rather than use it as currency.

Food works better as a currency paid to a traveler. It would be paid from a farmer. A goat, cow, or sheep would be better, but I can't see them as commonly traded by travelers. A traveler might trade excess wheat paid by a farmer for an animal from a herder.

### Services

A traveler might pay with mail. Stop in at the local general store or inn. Perhaps they have some mail that needs taken to the traveler's next destination. The recipient would be expected to pay for the mail. Sender-paid mail wouldn't work because then travelers could just throw the mail away. But recipient paid mail gives an incentive for the traveler to make the delivery.

Similarly, travelers might pay with deliveries. But then the traveler would probably be expected to pay the manufacturer part of the cost of the item. The recipient would pay the the full price.

Travelers might commonly use a wagon so that they could carry a bit of freight. They might keep trade goods on hand. So a few knives or pans might be scratching around in the back along with a barrel of beer, some spices, and a few pieces of mail. The beer and mail are deliveries. The spices, knives, and pans are on speculation.

• +1: also your our "travelers" have evolved into "traders" there at the end. They buy in one place, move the items and sell for a higher price somewhere else. – Binary Worrier Mar 9 '18 at 12:45

It has been said a couple times I think, but I think considering your restrictions, ammunition may be your best option. It matches all your prerequisites:

1. Obviously ammunition is exactly that, ammunition. Usefulness should be self explanitory.
2. If society has really been reduced such a dwindling population and understanding of technology then it stands to reason that much of the ammunition will have been spent between the plague (for lack of a better word) and the violent days that followed. This already gives you an obvious basis for its value.
3. Faking ammunition is relatively difficult if you actually get to hold it in your hand, much like really money.
4. Bullets and shells are relatively small and transportation is easy as filling up a box or a bag or even your pockets. They are already comparable to coins in that sense despite being a bit larger.
5. It is decently durable for transport and trade so long as the primer isn't hit by anything or they don't get too hot.
6. As mentioned above, ammunition should still be around and the function and scarcity of certain types of ammunition even give you a basis for multiple trading values depending on the type of ammunition.

I imagine by that point that real bullets would be much more rare. The necessary precision to produce them just wouldn't be available unless you had a fully function factory that could make them en masse as much of that is automated today. That said, refilling shotgun shells is actually pretty easy as long as you have the appropriate propellant. Furthermore, I see no reason why they wouldn't start using muskets or black powder rifles. Many of those were made by individual gunsmiths by hand, and the ammunition is simple as filling a ball mold with lead. Taking another step down the line, anyone lacking ammunition would revert to melee weapons or more ancient projectiles like arrows and slings. Arrows are simple to make if you know how, and a sling uses any rock on the ground.

In the end you could have an ammunition currency system where each type holds a value comparable to today's cash bills (not necessarily proportional to value, just an example):

• Arrows = 1 dollar
• Musket ball = 5 dollars
• Shotgun shell = 10 dollars
• Low caliber bullet = 20 dollars
• High caliber bullet = 50 dollars

Obviously this means that the ability to produce your own ammunition/currency is still available, but the difficulty should be reflected in the value of each ammo type.

• This was going to be my answer as well, in the Metro universe (Metro 2033 novels and games), .762 cartridges are used as a universal currency within the metro, for the reasons you've outlined. – Orgmo Mar 9 '18 at 10:29
• Hey, yes, i've taken this in consideration. Only thing i don't agree with this post is this "3. Faking ammunition is relatively difficult if you actually get to hold it in your hand, much like really money.". it is not that difficilut. Imagine a bullet with a shitty primer or not enough gunpoweder inside to make it fly? ofcourse you can test stuff right away, but thats just wasting of money, its like i payed something 20 dollars, but i burned five to check if its real money... – Bora Mar 9 '18 at 13:30
• The relative value there is off - a single musket ball being worth 5 arrows? Arrows take a lot of labor to make, and don't often survive use. A musket ball just needs a bit of lead (recovered from shot bullets or old batteries or anywhere) melted over a campfire and poured into a mold - they are practically worthless in comparison. – pluckedkiwi Mar 9 '18 at 18:52
• You could also use Brass (defined as spent shells), shotshells, and lead in this context as lower level currency. – Paul TIKI Mar 9 '18 at 20:02
• Counterfeiting ammunition is easy. Take a spent cartridge, fill it with sand, hammer a bullet-shaped chunk of metal on the end, and you've got something that will pass a casual inspection. – Mark Mar 9 '18 at 22:40

The main problem, I think, with most of the suggestions made by other folks is the items they suggest have an inherent usability that might tempt or require you to use them for their original purpose as opposed to a trading medium. If a bottle of decongestant will get you five pounds of meat, but you have a real stuffy nose, you may choose to destroy the "currency" by taking it.

A better common medium would be something relatively useless for any other purpose, hard to duplicate, and easy to carry.

In honesty, bottle caps would make a pretty damned good one, but it's been taken.

So I'm going to suggest car keys.

Cars are presumably no longer a thing, and the ability to make more keys is gone. Most car keys are made of aluminum or other non-rusting metal, so they'd still be around. They're relatively rare, and save for someone finding a lost auto dealership, there won't be some massive glut driving down the market. And they're certainly easy to carry.

• This is the best answer I've seen... – Erin Thursby Mar 10 '18 at 15:23

Aluminum

Mining new aluminum is difficult, and processing ore would be really hard in your setting so you are limited in supply to what you can find lying around. Melting it down is certainly possible, but not totally trivial.

It is certainly useful. It can be melted into tools, devices, weapons, what have you. Again, not totally trivial, but it is doable for someone with access to a furnace. It melts at a lower point than iron, so that helps.

It's lighter than iron, and fair amounts can be carried easily. And unlike iron, it doesn't oxidize readily.

Smiths with the ability to reduce scrap aluminum into bars or ingots would become the new bankers. They would be able to take scrap by weight, melt it down, and return it to the person who brought it, deducting a healthy commission, of course.

Rendered bar stock or coins could be traded in your settlements, and even be taken and traded to others. Your people would be able to scrounge for "raw" aluminum, like cans, car parts, old airplanes, etc., but this would, obviously, less immediately negotiable until it got processed. The immediate area of the town would get scrounged clean pretty fast, so those who want to go find more would take their risks like gold prospectors of old.

• Aluminium was initially treated as a precious metal, as it was very hard to produce. Only, with the Heroult-Hall process it became possible to produce Aluminium on an industrial scale, and the preciousness was lost. See en.wikipedia.org/wiki/Aluminium – Dohn Joe Mar 10 '18 at 0:27
• That's actually why I proposed it. Existing scrap aluminum will be around and it isn't as hard to melt down and re-use, but to produce new aluminum from ore is going to be much harder. You end up with a resource that is plentiful enough in a post apocalyptic world to be used to make useful items, but it will be a finite resource and therefore suitable to drift slowly over time into something like a precious metal. – Paul TIKI Mar 12 '18 at 14:19

Not one currency, but many...

Reloaded-Amumunition, black-powder, primers, antibiotics, painkillers, batteries, light bulbs, seasonings, salt, sugar, nuts, hard-tack, water purification pills, matches, toilet paper, moonshine, canned-vegetables, knife sharpening stones, nails, fasteners (nuts & bolts), copper-wire, rope and dried-meat.

In the future, currency must have real value and that value will fluctuate with the seller's need. Best to carry a little of everything.

• Hello Henry.... Yes, i agree, but as i stated in a comment above, the technology and organization just doesn't suffice to make complex pharmaceuticals, bullets, or any other industrial product. At least for a mass production. And, as described in post, it is happening a hundred years after the world stopped, so most of the things by then, if not used and destroyed, are decayed an have no use. – Bora Mar 9 '18 at 1:10
• These are barter goods, not currency (though I think they're a great idea. – RonJohn Mar 9 '18 at 4:01
• @Bora "At least for a mass production." That lack of mass production is what makes them so valuable due to small-scale production. – RonJohn Mar 9 '18 at 4:03

Since you mentioned that that solar cells etc still exist, I'm almost surprised noone mentioned this yet:

Batteries or any other kind of Power-Cell

It fulfills your needs and in addition has a few additional perks that might allow for interesting ways to deal with money:

• Empty power cells are only almost worthless - people with the technology to recharge them, will be quite eager to get them, so there is still some market value
• Not everyone might be able to tell the difference between recharable and non-rechargeable cells
• The Equipment to actually recharge cells practically becomes a gold-mine

• Obvious practical use, in that you can power all kinds of 'ancient tech' with it.

• After 100years most old cells will be in bad shape - but some should survive

• Charged cells are impossible to counterfeit, any light-bulb (or similar) can tell whether something gives of power or not. (This makes trading with uncharged cells even more risky & suspicious)

• Relatively small & not too heavy

• Durability might be the 'biggest issue', they wont fall apart but you shouldn't get them wet etc.

• Darn it, you beat me! Something like a volt-meter would be really useful as a way to test the batteries. Also, depending on how far in the future the collapse happened, there might be some interesting new battery technology available. Something like the Carbon-Proton battery might be well developed and mature, and could have a decent durability. All it needs are carbon graphite rods, a reversible fuel cell, and pure water. Someone with a little scientific know how could probably repair them without a lot of dangerous chemicals. – AndyD273 Mar 9 '18 at 15:48

What does something need to work as a medium of exchange?

1. It needs to be durable. Money that decomposes over the winter, or shatters if handled roughly, or can be eaten by termites isn't much good.
2. It needs to be scarce. Sand may be durable, but it still doesn't make a good currency, because anyone can go out and pick up a handful.
3. It needs to be resistant to counterfeiting. If it's easy for the average person to make copies of it, the above-mentioned "scarcity" requirement fails.
4. It needs to be fungible, ie. it's easy to judge the value of one unit of the currency against the value of another. This is where the commonly-suggested "information as a currency" falls down: it's virtually impossible to judge the worth of a piece of information.

Gold would make a pretty good currency here, but you've decided that you don't want it.

One interesting possibility, though, would be for the University settlement to issue "work credits": tokens that can be exchanged for a certain amount of research effort by the scholars there. Theoretically, any of the settlements could do this, but the University is best-positioned to make tokens that are hard to duplicate.

Durable? Stamp them into steel, or print them on parchment, or otherwise make them out of something that will survive normal wear.

Scarce? The University controls how many tokens are in circulation.

Counterfeit-resistant? The University probably has some tech that nobody else does.

Fungible? An hour of research is an hour of research.

• Good idea about the university! I've thought about it, and the reason i think it might not work is that that settlement is not "strong" enough to set conditions on whats worth how much, let alone control anything. If you've read "The Name of the Wind" by Rothfuss, its somehow like that there, that place has weight, but there is nothing stopping a lot more numerous and stronger force of angry people storming it and demanding satisfaction. People in this area aren't good with central government... – Bora Mar 9 '18 at 13:39

Why not use the American colonies' first common currency: whiskey? Back when states were issuing their own currency, many people found it easier to conduct business using whiskey than go through the hassle of trying to change coins or banknotes from another region into something accepted locally. Whiskey is durable, useful and easy to subdivide into whatever amounts you might want (anything from a keg to a shot). It's easy to transport and difficult to counterfit. It's also tricky enough to make that you don't run much of a risk of someone producing so much that they devalue the market.

• yeah, but you could drink half a bottle, refill with pee and have it away before the guy pops the bottle open. You could also just refill with water when swindling the guys you kind of like – Paul TIKI Mar 9 '18 at 20:29
• @PaulTIKI that is an issue today because you are not likely to ever find again the guy you are defrauding. But if you live in a small community only sheldom visit a handful of other local communities, if you piss people off they are going to find you and have you pay your lies... – SJuan76 Mar 10 '18 at 14:14
• Quite true. I'm thinking more along the lines of the freelance distributer, the traveling snake oil salesman, if you will. Think about it. whiskey has a value of X per bottle. You get some extra bottles and dilute your supply with 10 to 15% water. So you leave the factory with 20 bottles and arrive at the next town with 22, and no on the wiser. Move along to the next town. Market the one you fortified with something other than water as the extra special reserve, double the price, auction it off and get out of town. – Paul TIKI Mar 12 '18 at 14:28
• Love this. After living in Croatia for six months, I have to say the people of the Balkans will make alcohol out of anything. Heck, when I got stomach flu, my landlady tried to treat me with something brewed from local grasses. – KernelOfChaos Mar 13 '18 at 10:18

Seeds

Settlements of any size will need to grow food in order to survive. The ability to plant crops of edible food is imperative, as humans cannot live on the nutrients from meat alone. Hunting is time consuming and can yield in quantities that might not be sufficient to survive on. Even a primitive society can reliably plant and tend crops of fruits and vegetables. A more advanced society can increase that output, as well as grow food year round.

Seeds of edible crops are small and easy to transport. Depending on the seed, they can survive unplanted for a long time. Some seeds, like beans, peas, tomatoes and carrots, can stay viable as long as four years. Seeds like cucumber or lettuce can stay viable up to six years.

The rarity of a particular seed could make it far more valuable than another. Berries, which grow natively in the wild, would likely have a low value. However, tomato seeds, which are not native to Europe, would be much more highly coveted, and therefore more valuable.

I'm going to have to start by saying that you are rather confused.

As others have commented, commodity currency has to be useless. So the two requirements,

Has actual practical use and value to people in this environment

Durability, can't be fragile

are at some level incompatible. The problem is that once you start using something, you can't use it as currency, since that requires that you give the thing to somebody else. No matter how durable the object or material may be, if it is usable (and used) as a commodity, it has been destroyed as a currency.

There are a few examples of usable "currencies", such as cigarettes in Europe immediately after WWII, but these also show why the idea doesn't work. If a cigarette costs a dollar, and you give someone a dollar for a cigarette and then smoke the cigarette, the dollar remains as a value marker for another trade. If you give someone a loaf of bread for a cigarette, and he eats the bread and you smoke the cigarette, there is nothing left. This is not good for exchange, when the medium of exchange evaporates.

There are other problems with your scenario, and while you (as author) can write whatever you want, you don't seem to have thought things through. 100 years after the Big Dying, you want villages not to be self-sufficient in food. Veggies for meat, for instance. Let's say imported food amounts to 4 ounces per meal per person, 2 meals per day. Have you done the arithmetic? That's 50,000 pounds per 300-person village per year. Over degraded roads/paths in the face of widespread bandit activity. Well, it's easy to see how the bandits are surviving, but not how the villages manage.

Other answers have trotted out the idea of using ammunition as currency. Given 100 years since the Apocalypse, this fails on so many different levels. Ignore the whole currency/commodity issue. With the population dispersed into small villages, where is the industry going to come from? Smokeless powder requires large quantities of both nitric and sulphuric acid, and those aren't exactly craft products. Where does the cotton come from? (In principle, you could use wood chips, but they have to be ground exceeding fine to allow complete nitration, and that's not easy.) How do you expect to handle the plasticization of the nitrocellulose and the subsequent extrusion? If you don't do that stuff precisely, you'll get overpressure on firing. Even worse, where are you going to get primers? They need the same sort of chemistry as smokeless powder, PLUS precision metallurgy to fabricate and install the cups.

Plus, there's the whole issue of counterfeitting. Gold coins, for instance, can be checked for purity in a number of useful ways. If very pure, the classic bite test combined with weight gives an excellent quick test, while for lesser purities touchstones did quite well. Importantly, both tests are essentially non-destructive. How do you check a rifle cartridge for authenticity without firing it, which reduces its value to something near zero?

Oh yes, and there's a problem with gold, too. There's just too much of it lying around. All those cities which were depopulated had jewelry shops just waiting to be grabbed. While you could simply assert that such looting did occur during the Bad Times, and the resulting hoards were lost when the looters were killed, you'd need to specifically state it.

I suspect that you've confused the idea of a universal value token with currency. It's one thing to denominate value in terms of some reference commodity (in early days, it apparently started with cows), but having done so immediately produced trade in symbolic cows, not real ones.

Equally important, currency doesn't become terribly useful until trade is widespread and complex. Trading a ton of wheat for 200 pounds of meat from the neighboring village doesn't require currency, but a 3-sided trade of wheat for meat for cloth spread out over several hundred miles and several weeks (due to slow transport times) gets really inconvenient when attempted by barter.

Basically, you seem to have described a setup which makes currency irrelevant, and want advice on what currency to use.

You are looking for something exotic, light, possibly useful. As a currency, you need something that cannot easily be faked or duplicated, but is available in large enough quantities.

I offer pre-apocalypse ammunition. Bullets require metalworking that will not be available anymore, they are light, plentiful but in limited supply, and since at least some firearms certainly survived as well, in a life-or-death situation you are faced with the interesting choice of using your bullets or keeping them so you can later buy things.(*)

There are even different types of ammunition that can have different values, so you can circumvent the usual "bottle caps" or "gold coins" problem (ever had a D&D character hauling around 50,000 gold coins?

(*) a hundred years is a stretch, but ammo kept in good storage conditions can last decades. Under optimal conditions, a century is possible, though misfires and duds would be common.

• Ammo's a bad choice because it comes in so many varieties. If my gun's chambered for Remington .223, a handful of 5.56 NATO is useless to me. – Mark Mar 9 '18 at 5:39
• As a bullet, yes. But as a currency, it can have value, and sooner or later it will find its way into the hands of someone who can also use it for shooting. – Tom Mar 9 '18 at 11:43
• I don't think you realize just how many different sizes there are. Wikipedia lists about 350 entries for "common rifle cartridges" alone, and another 200 entries for handgun cartridges. A currency with 550 different denominations wouldn't be practical even if there were clear conversions between them. – Mark Mar 9 '18 at 22:36
• You are looking at world-wide. Within a given area, the amount of different ammo available will be much lower than that. It's not a good argument to say that communication will be difficult in a story because there are over a thousand languages in the world. Yes there are, but in a given place, the number is much, much lower. – Tom Mar 9 '18 at 23:29
• is it possible to recreate a bullet with that limited technology i mentioned? Ive been researching and can't really come to a comclusion. Primer is the problem... – Bora Mar 10 '18 at 13:43

Gold wedding bands for example have to be something you can find all over the western world, they're portable, wearable, you can thread them on a chain or keep them in a bag, they'd make great trade-goods even if you don't recognise them as de-facto currency.

They come in a fixed size and their value can continue to be estimated on the old Caret standard.

The metal is already worked and shaped and has a strong association with value from the get-go, If you need it to have practical utility, most of the various "jewelry" metals like Gold and silver are excellent electrical conductors and easily shaped. So they'd be potentially very valuable for maintaining any electrical hardware.

Attached to that, you can play with the idea.

These rich little kingpin characters of their own fiefdoms entirely covered in old-world bling and chains. Wearing their wealth literally on their sleeve. Echoing the Gangstas of the pre-apocalypse in a kind of twist on the spikey post-apocalyptic punks we normally get fed with Mad Max and Road-warrior.

I have a suggestion? Iron. It has utility, a set value (need x amount for y product), and it can be broken down to easily portable bits. Example, it takes about 2 lbs of iron to craft a decent surival style knife (iron not steel) and if i have a pound of iron i can trade that as currency for about half of what i could get for bartering that knife... Give or take a bit for variance in the barter system that would be predominant locally in a setting like that.

True Aluminum. Not alloys. Real aluminum is "pretty", useful for creating basic steels, and incredibly light for its strength. Pound for pound its stronger than steel, and rarer (assuming you could find aluminum foil in this world, now you have to make it into useable ingots.) If you doubt the use of aluminum, wiki it... You'll be surprised.

• I like this one too. Plus someone with knowledge of smelting would be able to turn even rusty metal into something useful, which actually would make reducing agents like coke valuable as a byproduct. This leads to secondary forms of currency. Clean iron is worth \$\$\$, reducing agents are worth \$\$and rusty iron is worth \$-\$\$ depending on how much work they'll need. Another nice thing about iron is that it's hardish to counterfeit, All you need is a magnet and you can tell if it's iron or a derivative, or something completely different. – AndyD273 Mar 9 '18 at 15:59
• Iron is ubiquitous, so not very valuable. The weight to value ratio is not favorable. While it could make a reasonable trade commodity a few thousand years ago (though still far too heavy - need finished products to have enough value to justify the weight), modern life has ensured that there is plenty of iron just about everywhere man has settled. – pluckedkiwi Mar 9 '18 at 19:27
• I disagree, respectfully, and will justify my answer thus: steel is ubiquitous, however its utility in a PApoc world would be limited by its alloy. iron on the other hand, pure iron, is unusual. When was the last time you saw a cast iron pot? Or any form of unalloyed iron for that matter. Iron "coins" of about 1oz each approx can be verified by magnet where alloys can't always be, they would be portable, and weighable. I stand by my answer as the only real self-backed, useful, and portable currency. It would take effort to obtain and utilize. – wolf Mar 10 '18 at 1:49
• Nearly forgot, theres also the "grinder test". An expert can verify a metal/alloy by watching how it sparks on a grinder, and alloys (including steel) would have limited use... Most have too much nickel, tin, or aluminum... Also... Answer edit – wolf Mar 10 '18 at 1:58

Certain books.

The kind that teach how to build stuff. How to make concrete. How to build a forge and make tools. How to make gunpowder and a alcohol still. How to fix a car and how to make a electricity generator.

Even today, these books make a very small percentage of the total amount of books. Libraries are full of self help books about building a positive image for yourself and how to deal with depression. Not so much with books about tanning a hide from hunted animal, or making electricity from a river.

Add 100 years of decay and ruin, and paper books of this kind will be near impossible to find and treasured as a important resource. One that is lighter than metal, so its easy to transport. Has lots of value and everybody wants it, so its easy to exchange.

The Old University can trade in tech because it can produce books, copies in fact, adapted to the new reality, short, practical versions of the originals. The "secret" tech of the Univerity is paper making and a human powered, Gutenberg like, printing press. The University is realeasing a very limited amount of books because keeping the supply low makes books more valuable and The University relevant.

• Nice answer. I'd argue that once I read a book, this one and all treating of the exact same topic kinda lose value, so you maybe couldn't trade some books with some people. And those people can train other without a book, so knowledge will spread anyway, albeit at a really slow rate. But this is definitely an interesting idea for rare tradeable currency. – Nyakouai Aug 9 at 7:23
• Certain books. Porno books. – Willk Aug 10 at 20:05
• Actually, thats not a bad ideea :) – Cristi Priciu Aug 11 at 18:14

What about cigarettes? They're portable, have a practical use for those who like to smoke; and you can use cigars as a more valuable "bill". They're not too durable but they're durable enough if you keep them in a bag. More can always be produced and i'm sure theres still some cig packs around from the old world.

• Cigarettes were commonly used as a form of currency by soldiers in the trenches of WW1, which is in itself a rather post-apocalyptic setting. At least up until you are relieved and you can go back to the Hinterland. – Dohn Joe Mar 10 '18 at 0:31
• Welcome to WorldBuilding Tobias! If you have a moment please take the tour and visit the help center to learn more about the site. Have fun! – Secespitus Mar 14 '18 at 8:58

Medicine

More specifically, general use antibiotics, especially in tablet form.

• Small and light to carry. Easy to count the tablets, or trade by whole bottles.
• Remain usable for a long time. Even though they will gradually become less effective, many types will last more than 10 years.
• Are very valuable: bacterial infections will be quite common in a world with general lack of hygiene and healthcare. A dozen antibiotics tablets can save your life.
• You'd generally want to keep some with you even if you don't currently have an infection. Thus, most people would be able to pay if desperate enough, and would be happy to get some more tablets as a payment.

Items of practical value which would be of use are not currency. They are barter items.

Barter items can ACT like currency but if they are of use there's a tendency to USE them, and their value disappears.

The hides that you speak of were mainly used as currency out west in the United States because there wasn't ready money out there, and they were to be converted to cash back east where there was a use for them (shoes and other leather goods). When hides were used with a fixed value in rural communities, they were as much a barter item as they were considered money.

The best suggestion I have seen on here is keys from @VBartilucci. Everyone, upvote @VBartilucci because I can't take credit for this idea! I'm going to just use that as a jumping off point. Old keys could work, and even if you made new ones, you'd have to have aluminum to that, which would mean something like old soda cans and other things would instantly have value. There may be rare places and machines that can machine keys, but they would need the raw materials to do that. Aluminum IS useful...Keys are also useful, so if you did have a lock made for something, and a key to fit it, that would be your last key.

I can see that seeping in culturally. "Man's down to his last key, if he trades that away, he can't even unlock what he bought before." (Might just be symbolic, might not even unlock anything, could be passed from their father or mom). The last key might be a simple one, like keys from several hundreds of years ago when lock mechanisms were simpler or even a tiny key to a music box, or a faux golden key jewelry--mostly anything that doesn't look like the standard machined key from our era. It may or may not actually unlock something. They may be less valued than the obviously machined ones from the time before, because they are easier to make. But I would view anyone who has a lot of these types of keys with suspicion as I think that it would be something that a person would not give up except in death. These might be made of any material because they wouldn't be something you would want to trade away.

Were I the University, I would be machining keys with the sigil of the university. Keys might be used commonly in the larger area, but I can see a currency exchange program--you bring in common keys, and you get University keys of equal value (perhaps a little less owing to exchange rate). And University keys are the only accepted currency within the township.

Counterfeit Test is a simple magnet. Try it at home with your own keys. Aluminum doesn't attract a magnet. Iron, nickel, cobalt, gadolinium, neodymium and samarium are magnetic. There's going to be a lot of old iron laying around but things like gold, copper, silver--none of those attract a magnet. Those three are relatively rare compared to the other metals, so even if they are used to make keys, it's still a way to trace value.

As for keys being "faked" the level of tech you're talking about is low, and the skills and equipment needed are specialized, so anyone making machined keys will be making a limited amount.

Ammunition would be much, much rarer than keys, and harder to make. While it can be faked, it's also very useful (if you have a gun). But this means that ammunition isn't money. It's a barter item that could be used to trade for currency (like keys) or other items. How much use is ammunition if there aren't that many guns? And if you have a gun that takes rare ammunition how much use if that gun? As others have pointed out, checking for authenticity of bullets uses the bullets...

Batteries look like a good idea, but after 100 years, well...

### Days or hours

Everyone can do something. Time is not something easily broken or stolen, some people have more valuable skills and would get more out of their time obviously, but that plays well to the nature of currency exchange. People would trade days or hours of their own proficiency and skill.

Some would trade chits for the days of others and become wealthy making good exchanges. The chits could vary from place to place easily without diminishing the value. A simple and visible penalty like a scar on the arm could easily be given to one who 'stole' by not providing service, not unlike cutting the hand off a thief, but a clear sign that... this person with five on their arm may not be trusted to be honest.

There's room for abuse and theft, which is part of a rounded system while still having broad use. Different villages could easily have community boards, they might have entries like "five days of cow milking and one day of manual labor work in exchange for a winter blanket, see the local chitmaster to claim" or "woolen undergarments for the winter, prices vary from three hours housework (socks) to many available days work needed for more extensive wardrobe additions, speak to Bob at the Inn of Shepherds or his wife Jill to claim"

• Welcome to WorldBuilding.SE! Interesting answer. By the way: there is a little help bar at the top of the box where you type your posts. That can help you with markdown. For example you need to hit Enter twice for a paragraph or add two spaces at the end of a line before hitting Enter once to get a soft linebreak. You can also click on "edit" on other people's posts to propose an edit or to simply check how they did something. If you have a moment please take the tour and visit the help center to learn more about the site. Have fun! – Secespitus Mar 14 '18 at 8:57

Ground Spices

Especially medicinal ones like Sage, Thyme, Oregano. Useful for flavoring food and for antioxidants and antifungal/bacterial properties etc.

Pachinko balls. Small, durable, hard to manufacture. Useful as ammunition in slingshots, with added benefit of being reusable if you dig them out of the target. Can be used as ball bearings, etc. Only downside is that these are only abundant in Japan. Set your post-apocalypse in Tokyo and you're set.

Well, settlements ne ed to grow edible plants and breed edible animals. So corn, potatoes, tomatoes, cucumbers, chicken, cows, pigs, horses. Sometimes deer, boar etc... For hunting and fighting people would use something that cannot be depleted or can be easily refilled. Say goodbye to guns. People would use Fiskar tools sport bows and crossbows made from aluminium titanium or carbonized alloys from prefall era. Also improvised handcrafted weapons. Any other goods can be subject of trade. Luxury goods, craft goods like baskets, plates, cups. Hard to get herbs for healing. Seasonings, salt. Maybe dried meat. Products of farming :dried mushrooms, corn, wheat, rice. Jewelery. Some prefall era nondecaying things like plastic bottles canisters. Scavenged medicines, basically anything that would make your life better. But in a society this small you cant afford to rely on someone else. The things necessary for one settlement to survive must come from that settlement. Otherwise people would just pack up and move their asses somewhere greener. One currency isnt a good idea a) it attracts unwanted attention 2) is just added weight with no real purpose. But if a hunting party comes to town with lets say 50 pelts, i can imagine people will be grateful their asses Dont get all icy during winter and would happily share some food surplus in exchange. You need to choose whether your society thrives to better future or declines to oblivion as common currency is usually a thing in a thriving culture. Also human work will be on demand. It was usually a thing to get paid in food or bed for your work. Grandma needs new roof? Great you've got yourself a meal and bed for a few nights . Sorry for my english, its not my native language plus Im lazy to go all Oxford on my smartphone :-D

• I am not sure I follow your reasoning. If I have only fur to trade, it means I am out of business in warm climates and seasons, while currency doesn't care about them. – L.Dutch Aug 8 at 7:51
• @L.Dutch in warm climates you'll get hides for leather, which is useful regardless of weather now or later. In warm seasons with the expectation of cold seasons ahead, the people who didn't die of cold last year might be interested in stocking up on supplies ahead of time. If you arrive in a townful of idiots, come back in winter and loot their corpses. – Starfish Prime Aug 8 at 8:49
• @Viktor: please use paragraphs. They make posts much easier to read. – Starfish Prime Aug 8 at 8:49