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Picture the future, where man kind has spread out across the galaxy.

What would be the most precious and sought after materials?

Today it is metals like gold and platinum that are most sought after. Would this still be true in the future? Am I right in thinking gold would be more abundant in space and therefore less valuable?

I considered that something like antimatter or dark matter would become highly sought after, but then I discovered that apparently there is plenty of dark matter out there. Still not sure about antimatter.

I have been thinking that the rarest materials in the universe would be the ones that have the most protons and neutrons - but I need someone with more knowledge on the subject to weigh in.

What would be the new gold of the future?

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    $\begingroup$ Any issue with a non-material answer? In an economy where any material can be 'replicated', does it stand to reason that information or energy would be more valuable than material? How about time as the new gold? $\endgroup$ – Twelfth Dec 9 '14 at 21:06
  • $\begingroup$ I read this question as, "What would be the most valuable (luxury) resource in a galactic empire" - Should it also be wearable or shown on your person, as a display of wealth, like gold is currently? $\endgroup$ – DoubleDouble Dec 9 '14 at 22:02
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    $\begingroup$ Precious in what sense? Precious to scientists? Precious to manufacturers? Precious for economies in the sense that rare materials replaces a gold-backed system? As I remember we stopped using the gold system and we are now using a fiat system. For reference The Bretton Woods system ended on August 15, 1971, when President Richard Nixon ended trading of gold.economics.about.com/cs/money/a/gold_standard.htm. Fiat system is the value of money is set by the supply and demand for money and the supply and demand for other goods and services in the economy. $\endgroup$ – tls Dec 10 '14 at 4:20
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    $\begingroup$ The 4X game Endless Space introduces a foreign alien material that becomes the rare and sought-after material for research and development. $\endgroup$ – Gusdor Dec 10 '14 at 8:23
  • $\begingroup$ Unobtainium - or whatever the source of energy is for interstellar drive $\endgroup$ – user2051 Dec 11 '14 at 1:01

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As you say, the most sought after materials are the rarest. You also correctly assume that the rarest materials are often those with the greatest molecular mass. This is because it takes a much, much bigger star to produce heavier elements. For example, say in a sector of the universe you have 100 stars, of which:

80 are average sized (produce elements up to iron)
10 are dwarves (almost useless in terms of element production)
7 are massive (all elements up to lanthanum)
3 are supermassive (all elements)

All of these stars will produce helium. Not very sought after, you'll have incalculable amounts of it.
90% will produce [up to] iron. Again, not very valuable in terms of rarity.
Just 10% will produce [up to] lanthanum. You're getting more valuable now.
Lastly, only 3% will produce anything after that. These are the most valuable elements. 2

Therefore (in theory), in such a sector, most elements after lanthanum would be the most valued. However, in practice this would be a bit different. Let's have a look at Earth, where uranium is more common than gold, yet it's heavier so by the above definitions should be more rare. This is because the elements produced by stars in the early stages of the universe were scattered around and as such when the earth formed, it had a bit of an odd distribution of elements, and still does.


You're right in that things like gold would be more common in space (it's rare on Earth because the Sun doesn't produce it, for the most part). So, in theory, the most valuable elements would be the heaviest. To be on the safe side, say the most valued would be after actinium, and obviously I can't say exactly which element would be most rare because of the slightly random distribution. However, if you base off these theories, you should be reasonably sure of it.

However, you will also need to note that value depends not just on rarity and supply of an element, but also on demand (thanks to Philipp for bringing this up). If, for example, uranium and einsteinium are both very rare, but there is a higher demand for einsteinium, then it will be the more valuable of the two because suppliers will recognise the market and push prices up.


As an added bonus from the comments: these will be the rarest elements, but how do we get them? As HDE says, taking a trip over to the nearest stellar remnant wouldn't be the most fun of adventures, nor would heading for a black hole to collect the remnants of a supergiant gone supernova. Fortunately, there is a solution.

It lies in the way new stars and systems are created. When a star dies, it leaves behind a dwarf, neutron star, or black hole. Either of the first two are, over (very very very very long periods of) time, broken up1 and they form nebulae, the interstellar clouds from which new systems are created. The elements that end up in each planet of the system come from this cloud. So, if you visit the nebula of a past supergiant that didn't go supernova, you'll find all those lovely rare elements there. Black holes, however, may become an occupational hazard.

1: Physicists, don't batter me: I only have very limited knowledge of this process.
2: Stars will only produce elements heavier than iron at the end of their life, releasing them on supernova because they are made in the core.

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    $\begingroup$ Regarding gold vs uranium: this actually has to do with their solubility in iron (see physics.stackexchange.com/questions/144758/…) $\endgroup$ – Anton Dec 9 '14 at 16:27
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    $\begingroup$ Actually, the relative abundance of gold vs. uranium in the Earth's crust is different than their relative abundance in the universe due to chemistry and planet forming/evolution. For a more detailed discussion of this see In the earth's crust, why is there far more uranium than gold?. Arrrg. Looks like Anton beat me to this comment by 30 seconds. $\endgroup$ – Makyen Dec 9 '14 at 16:27
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    $\begingroup$ The main mechanism for getting material from a star out into the nebulae around it are solar winds, novae, and supernovae. The latter is the only way to get elements heavier than carbon out, as the heavy nuclei are made in the core. Red giants have massive solar winds that can blow some lighter things out. $\endgroup$ – Oldcat Dec 9 '14 at 23:17
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    $\begingroup$ No star produces gold during its regular lifespan. Anything above iron is produced when the star goes supernova. Gold is rare on earth because most of it sank towards the core. $\endgroup$ – mic_e Dec 10 '14 at 1:14
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    $\begingroup$ What this answer forgets to address is that value depends not just on supply but also on demand. When element A is three times as abundant as element B but there is 10 times as much demand for it, it will be considered more precious. $\endgroup$ – Philipp Dec 10 '14 at 16:15
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If you want to stick to raw physical materials, depending if your civilization is still limited to fusion or antimatter reactors for moving about, one might guess that rare isotopes used in fusion or magnetically sealed bottles of antimatter could be valuable.

But really, I think everyone is thinking a bit too much inside the box here. If you think about it, the kind of civilization that can even conceive of traveling galactic distances would not, in any significant fashion, be material-constrained.

To give a simple example, consider the most used metal in the world, iron ore. The world currently produces about 3 billion metric tons of purified iron per year, with known reserves at about 80 billion (more could be found with a more determined search). To put that in a cosmic context, a single large asteroid from the Asteroid Belt called 16 Psyche is believed to contain 17,000,000 billion tons of nickel–iron, so a single asteroid could supply the world production requirements for several million years. This holds true across all the metal groups.

So the resources at our disposal are truly astronomical in size. Of course, the rate of usage could scale out as humans embark on more and more ambitious projects (compare Columbus' ship Santa Maria with a modern supertanker or nuclear aircraft carrier), but it is unlikely that the physical resources will be the main limitation.

I would suggest that instead the most desired resource will be matter so arranged as to be capable of generalized problem-solving. Which is to say, matter in the form of minds, be they squishy human brains or artificial computronium.

It would make no sense to mine anything in one solar system and use up vast amounts of energy to schlep it over half-way across the galaxy. You can always find some frozen rocks to mine nearer, and millions of times cheaper.

However, some brilliant live physicist, or an AI capable of amazing feats of reasoning might just justify the amazing effort it would probably take to move things across quadrillions of miles at a significant fraction of the speed of light (or somehow warp spacetime for FTL). Perhaps you don't even need to send the actual mind across, just the information. Scan the physicist, beam the relevant information over, and he gets "reincarnated" at the destination.

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  • $\begingroup$ I suspect information in general would be valuable, not just in the form of minds. $\endgroup$ – Brendan Long Dec 9 '14 at 22:37
  • $\begingroup$ @BrendanLong, of course but the question was about precious materials. Not sure a high-intensity beam of photons travelling between star systems would qualify. $\endgroup$ – Serban Tanasa Dec 9 '14 at 22:59
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Yes, heavier elements will in general be more rare and thus in theory more valuable. However, at a galactic level, it matters what those elements can be used for. if all you have is a heavy metal that turns you vault into a radiation chamber, it's not that great.

Things that produce great energy will be very sought after. especially things that can provide energy to a ship between stars. Solar power is great when you are near by but there is a lot of space out there. Maybe some elements will turn out to be great in alloys to help capture energy from solar winds, that would make it more valuable.

Gold is pretty, safe, easy to manipulate(soft) and until fairly recently in human history only rare (not needed for more than decoration).

I suspect that biological specimens are actually going to be more valuable. Whether it is a toxin or a stay young protein. And the harder it is to reproduce artificially (if at all!) the more valuable it will be.

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First things first: water and food.

A galactic empire would be very much like a desert empire - a hell lot of NOTHING with an oasis every once in a while. Water planets like our dear old Earth are an exception, not a rule, and without water it's currently impossible (and most likely will be very hard in the future) to grow food.

So on most planets water would be imported and hauling enough water to sustain a whole city through half of a universe won't be cheap, so the water itself would be extremely expensive.

Now that we've paid a small fortune to eat and drink, what do we need? Energy.

In a galactic empire energy can solve pretty much any problem. Need a shelter? Create a force field. Need to go somewhere? Something has to power up your space ship. Need some item? 3D printing! Want to shot someone? Laser is your friend.

So your energy source will be another valuable thing. At this point it's pretty much nothing more than a name (and maybe some plot device). Call it Uranium, Darkmatterium, Bullpooperium, whatever. What's important is that demand for it will be infinite, so no amount of supply will satisfy it, driving the prices up.

The rest is a question of how you set up your world.

Here on Earth raw material aren't actually that expensive - it's the processing and the middle men driving the prices sky high. In your galactic empire both factors depend solely on your imagination.

Next on the list are political issues - look up extermination by hunger to see how to create artificial scarcity. On the other hand the government may subsidy something to make everyone use it (for example to establish ubiquitous surveillance, push some company out of business, or simply to poison everyone).

Last and least important are actual supply and demand. Other posters here covered supply quite well - I have nothing to add. As to demand - people in the real world aren't rational about it. Why would people in your story should behave differently? If you don't believe me go to the closest shopping centre and check out brands like Hugo Boss. You'll be shocked.

Summing up - water, food and energy are essential and hard to get, because we as a species ALWAYS want more and more of it. As to the rest - you can explain any shortage or overabundance with politics and corporate interests. And I advice you to focus on that - whether we like it or not it makes more interesting story than quoting scientific statistics.

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    $\begingroup$ Of course without oxygen, even plentiful food and water won't do you much good. Hydrogen is plentiful, oxygen less so, and hydrogen + oxygen = water. $\endgroup$ – fluffy Dec 9 '14 at 19:45
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    $\begingroup$ Good point. The supply is scarce and demand infinite. I'd say your comment is worthy to turn it into answer, you'll surely have my upvote :) $\endgroup$ – Darth Hunterix Dec 9 '14 at 20:10
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    $\begingroup$ "on most planets water would be imported" Are you sure we wouldn't just avoid settling worlds without liquid/ice water? $\endgroup$ – TylerH Dec 9 '14 at 21:58
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    $\begingroup$ While liquid water might be rare the makings of it are not. It's hydrogen (most of any gas giant) and oxygen (one of the major components of rock.) $\endgroup$ – Loren Pechtel Dec 10 '14 at 1:13
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    $\begingroup$ "Water planets like our dear old Earth are an exception, not a rule" this is something we do not yet know. Planets with abundant liquid water might be rare, but water itself is fairly common either trapped in the rock, frozen, or as vapor. And it's easy to make, hydrogen and oxygen being so common. The problem is not lack of water, the problem is lack of cheap energy to extract and purify it. $\endgroup$ – Schwern Dec 10 '14 at 19:41
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Obviously, most precious is the spice, which you can only mine on Dune, and which allows navigators to calculate hyperspace jumps. I thought you knew that. :-)

Really. With advanced technologies, and different civilizations, many very rare substances can be created or grown, with very special properties.

Elemental materials, which can be found around any average sun? Not very rare.

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    $\begingroup$ the spice must flow... $\endgroup$ – Jimmery Dec 10 '14 at 9:08
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Some materials, like gold and platinum are precious only because of our history, not because its use or demand. The truth in economy is things only have value as have people willing to posses it, the demand. Precious metals have demand because they are a sort of universal currency, and giving the culture of the galactic empire anything can be precious. A not useful material, where the accumulation do not compete with the industry have some preference over needed materials, so probably gold will remain as a universal currency for humans.

The leading technology of one civilization can make some artificial materials, like doped silicon, graphene, some ceramics, superconductors, quasi-crystals and its raw materials, like rare earths to be in high demand, rising its price even above gold. There are many material options demanding only a fictional technology what consume a large amount of them. As we have a universal lack of heavy elements, like rare earths, is highly probable the empire to have a big demand of a mix of them, and then high price. Unless graphene or other artificial form of a abundant element could take the place.

Antimatter will be desired only if we can use in something important. As a dangerous thing, I can see a highly expensive and controlled element, like uranium today, but not a new universal standard.

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  • $\begingroup$ There's actually a fairly high demand for gold in industrial applications in computing and for space-faring objects. $\endgroup$ – TylerH Dec 9 '14 at 21:59
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    $\begingroup$ Not really. Wikipedia says "Only 10% of the world consumption of new gold produced goes to industry" $\endgroup$ – Cochise Dec 9 '14 at 22:08
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    $\begingroup$ Doesn't take away the demand. If the cost of gold wasn't so high (because of the demand) it would be a much different statistic. $\endgroup$ – DoubleDouble Dec 9 '14 at 22:18
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    $\begingroup$ @Cochise That's still 250 metric tons every year. Considering how thin layers of gold are in industry applications, that is a lot of gold. Over $43 million worth, every year. $\endgroup$ – TylerH Dec 10 '14 at 3:38
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    $\begingroup$ @TylerH BTW, according to coinapps.com/gold/gram/calculator 250 metric tons of gold is worth almost TEN BILLION dollars. Yes, that is over $43 million. $\endgroup$ – Dronz Dec 10 '14 at 18:43
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The value of a material will be based on both it's utility and it's scarcity. If some substance is necessary for something like interstellar travel, it's going to become the most precious material unless it's exceedingly common (e.g. iron). Or it can be precious if its useful for life extension or something like telepathy.

Scarcity may be more than just lack of abundance. Many minerals elements can be reused or reclaimed, but if something is used up everytime it is used, than that leads to more scarcity. Or maybe it's a life form (anything from a virus, or bacteria to a fully sentient being). Ultimately, Life IS the most precious thing in the Universe.

A great example of all of this is from the novel Dune (Frank Herbert). The 'spice' was a special substance that granted extraordinary mental powers, from telepathy and seeing the future to "folding space" to allow interstellar travel. It was also the product of a life-form that was only found on one planet in the galaxy. Essentially, the entire galactic civilization was dependent on it. Therefore, it was the most precious substance in the universe (which made the basic plot completely unrealistic, but the concept was so powerful that its become legendary). Another example is the crystals from The Crystal Singer (Anne McCaffrey)

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  • $\begingroup$ I don't think the spice was used to fold the space time, but it was needed by the navigators to maneuver the FTL ships safely (because of prescience, I think). $\endgroup$ – kutschkem Dec 10 '14 at 9:28
  • $\begingroup$ @kutschkem: I think that's right too, by my bad memory. But think, if they didn't FTL before spice, then how did they get to Dune in the first place? $\endgroup$ – Zan Lynx Dec 10 '14 at 17:25
  • $\begingroup$ @ZanLynx Not safely? ;-P $\endgroup$ – kutschkem Dec 11 '14 at 9:34
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Everything is possible with little bit of sci-fi. But my idea is still plausible given current science knowledge and hypothesis.

There is nuclear physics theory of Island of stability which supposes, that there should be really heavy particles with long half-live of such element. But, we were unsuccessful to find them yet.

Lets say the theory is right.

Lets say this particle can be (and is) used to interstellar space engine.

Lets say there is region in our galaxy where exist the heaviest possible stars, and here such particle is naturally produced.

Now you have some scientifically plausible (but totally not probable) material which could be mined by Galactic empire

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    $\begingroup$ Sounds like Samuel R. Delany's novel Nova $\endgroup$ – Don Wakefield Dec 9 '14 at 20:13
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What is sought after, is entirely dependent upon the seekers. Reasons to seek, desire, covet, or value are not universal. There is no way to predict what people will value in the future. Economics masquerades as a science when it is really an attempt to justify and fixate thought on current systems which tend to be abusive and unsustainable. Assessing the prospective trade value of the galaxy's basic elements seems to me part of that misguided way to thinking. However:

Elements high on the periodic table will statistically be the rarest overall, and some might value them for that reason alone, or for their unique properties (for example, in some cases, they release more energy in reactions), but that's just one way some might decide to value them.

I may be out of date on antimatter, but last I heard, we didn't know how much there was out there, and thought perhaps some entire star systems could be made entirely of anti-matter. Anti-matter could perhaps be valuable fuel if controlled anti-matter reactors were feasible and developed.

The question seems to limit itself to base elements. Overall, I would think that the most useful and least common things would be healthy sustainable enjoyable ecosystems, life forms, positive culture (arts, freedom, entertainment, good company, leisure, peace, safety, justice, mental health) and useful durable technologies.

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A galactic empire will have the same demands we have: energy and transport. Cheap, clean, efficient, abundant, safe energy and transport and anything that helps produce them.

Why energy? It is labor saving which means more production which means more leisure time. It powers your transport and thus your economy. It lets you transform matter to reduce scarcity.

Why transport? Every step of every material process involves "and then you have to move that material somewhere else". You can't have an interstellar empire without an interstellar economy and that means interstellar transport. And, let's not forget, transport means freedom and leisure.

Let's take ArtOfCode's elemental supply argument as an example. With enough energy, you can make scarce elements through fusion and fission. As energy gets cheaper, at a certain point it becomes more economically feasible to manufacture rare and exotic elements by smashing atoms than by mining and moving them around.

Speaking of mining, Serban brings up a good point about how lucrative asteroid mining could be, but you need a lot of energy to get to the asteroid, work on it, and the transport to move them around in anything like a reasonable amount of time. Even anti-matter can be manufactured, it just takes a tremendous amount of energy.

Water and food are excellent considerations. Water is the limiting factor for producing food. Water is easy, you either make it, extract it, or purify it; hydrogen and oxygen are everywhere, all you need is the power to do it. The Australians figured this out and now build renewable energy plants to go along with their desalination plants.

Energy and transport, but the question was about materials. What sort of materials would produce cheap energy and transport in a galactic empire? I wouldn't hazard a guess, transport, material science, and energy technology advance so fast. For example, the last ten years has seen a sudden spike in demand for rare Earth minerals to make our tiny, efficient computing devices and batteries. Could that have been predicted a hundred years ago? Roll the clock back further and consider aluminum: who would have thought in Napoleon's days that a metal once considered more precious than gold, would be so cheap and abundant that we use it for disposable cans? The best scientific minds once thought the Sun and the age of the Earth was a paradox: how could anything produce that much energy for billions of years? Then we discovered fission, and then fusion. Who knows what next?

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Very compact or complex items, not piles of raw material

I believe that in a realistic setting, any special raw materials would not be precious in any interstellar setting. For example, gold can be trivially made by any space-level civilization from lead. For us right now it's cheaper to mine existing gold than to transmute materials, but if we had a pile of gold in Alpha Centauri, then it would take more energy to transport it here than to make it locally - so the import value for gold would be zero. Without magic FTL travel, interstellar spaceships would consist of mostly fuel. If you'd be spending 99 tons of fuel for every ton of cargo, then anything that's not 100 times more valuable than spaceship fuel isn't worth transporting at all.

The same goes for most items - if the destination has any available material, then it's reasonable to make everything there and transport only the bare minimum - some "bootstrapping" robots to make the machines that will make the actual product from local matter. it would be quicker to make a spaceship than to bring one that you have elsewhere, and

From a trade perspective after a location has been "started, then it would make sense to transport and only very compact or unreplicable or unique items - i.e. antimatter as a compact storage of energy, sentient beings, nanobots, artwork, genetic or industrial information, or if you want to keep the means of production secret (e.g. military gear). So all of this is low-weight "parcel delivery" or transmission of information or valued data.

For all other things - water, food, rocket fuel, gold, guns, uranium, spaceships - it would make sense to bring them to a place if you want to "sponsor" that place for strategic reasons, but it wouldn't make sense to have a "trade route" where you ship bulk stuff in both directions.

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Some others have alluded to it, but I'll state it right out. We don't know.

The most valuable material could and probably will change depending on the culture and technology of this empire, and even depending on various worlds within the empire. If you're looking for a common currency, easily portable and subdivided, I'm going to agree with some of the others and say 'energy'. Energy is always needed, everything has energy, and most things can release energy with sufficient technology.

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A type III star produces high metalicity solar systems. However even with the sun being like this earth needed a oxigenation event that lasted for a couple of billion years to multiply the number of metals into the 4500 known naturaly producing metals. So it is not only the star type (metalicity) that will produce the metal richness of a solar system but the interaction with other chemical components with the existing ones in the planest created. So there could be unique precious metals (scarce) as per their use in certain planets given the unique chemistry that has taken place in each planet.

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The most expensive elements are going to those that are rare and useful in building spaceships and habitats etc..., Niobium & Rhenium for high temperature alloys, Tungsten and Titanium for strong alloys, Indium for touch screens, Gold and Platinum as conductors, are the ones I'd be looking at first.

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  • $\begingroup$ late to the party, but nice answer :) $\endgroup$ – Jimmery Aug 9 '17 at 23:39
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The densest materials we can transport.

In the future we will probably master e=mc2. Meaning we will have a star trek replicator like device which can make anything, but more importantly dissemble any object into energy with nearly 100% efficiency.

The primary concern in the future will be energy. Everything needs it, and large ships need it even more so. The more volume an object takes the less they can transport. If you can convert any material to energy then your never out of fuel. Light elements would take more than dense ones per unit of energy.

The densest materials will provide the most energy per cubic inch of space.

Therefore as we advance in technology, getting closer and closer to blackholes,neutron stars, and etc make the most sense. Of course it will take magnetic confinement to keep the material from expanding as it moves away from the gravity of the blackhole or etc.

The best material will expand at just the rate they consume it at so it will never get significantly bigger in volume.

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The new gold of the future?

My suggestion is not material per se (it has mass, but very finite dimensionality) and is therefore easily transferrable.

Let me take Adam Millers response a bit farther. Every response to this post involves energy to do work (a simple definition of energy is the ability to do work). Every sophisticated society generates or buy way of purchasing generates energy (OPEC is having hard time due to the United States' / Canada's new found oil, one of the chief concerns surrounding greenhouse gas is the cost of energy production, further second and third world nations are have trouble with climate accords due to growing industrialization which centers on energy demands). So if energy is useful across societies there would be demand from menial laborers, to starship mechanics, to painters.

Demand for energy is not infinite it simply has a high limit. Every action taken by an individual or group has a finite energy requirement and a limited number of actions may be taken over time (and no E=MCˆ2 is not the exception to energy use it further reinforces the argument). Further, since there is an upward bound on the amount of energy accessible (E=MCˆ2).

Energy is divisible and discrete in quantity. 8 Joules is 2 * 4 joules is 2ˆ4 joules. Energy is complex as it can be used in most everyday process (keeping warm, keeping cool, in advanced civilizations transmuting matter). You can't forge energy, just the measurement of energy (so using a neutral parties energy measurement device is valid).

Energy is also transmissable over long distances. Think of the weight even if payed in hydrogen for a multi billion dollar asteroid (I don't know the physics off hand but compressing that much gas would be a nightmare). What if you were paid in gold, food, water, or any of the other commodities mentioned: the cost of moving that much mass over 4.3 light years for your next job would be horrific.

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  • $\begingroup$ The problem with energy is that isn't rare. This question is asking for a precious material. $\endgroup$ – sphennings Jan 4 '18 at 3:31
  • $\begingroup$ The down vote for this post is inappropriate: $\endgroup$ – Englishman Bob Jan 10 '18 at 15:34

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