# In the city of Altheia everyone dresses in copper: is this possible?

Altheia is the City of the Copper Folk. Its bishops and wise dictators believe that copper is the metal of gods, a holy item given to Altheians as a gift for their religious behavior.

Edit to clarify

The actual reason behind this belief is that in Altheia deaths have been lowered since the implementation of copper in daily life, mostly due to an increase in levels of hygiene as copper kills most bacteria, thus it was seen as an holy miraculous metal gifted from the heavens.

In Altheia everyone dresses in clothing made of copper. The clothes are not too heavy and they are certainly not armor but some small plates are used, not for protection but as decorations and accessories.

The territory of Altheia is so rich in copper that even the streets resemble blue oceans due to their bricks being made out of copper.

But there's one problem: the technology level of Altheia is similar to that of the ancient Greeks during the Roman empire.

How can they make copper clothing, if it's even possible?

• They did know how to weave soft ductile metals such as gold and silver in ancient Rome. Look up cloth of gold. Copper works just like gold, but for obvious reasons ancient Romans very much preferred to spend their effort on precious metals. A rich Roman lady wearing a gold fabric would make a strong impression; wearing a copper fabric, not so much. Plus, copper oxidizes easily and gets a sickly green color. – AlexP May 14 at 20:47
• @jdunlop -- For what it worths, copper won't "rust away" either. The oxidation of copper creates "patina", which serves as a protective layer. This is why you can dig up bronze objects from bogs and sea beds in relatively good condition where iron would rust away. – elemtilas May 14 at 22:00
• Not all metals are hard like steel, or brittle like magnesium. Some metals are soft, and can be drawn in very fine wires. The properties of interest are malleability and ductility. In particular, copper, silver and gold are very malleable and ductile. In practice, gold and silver cloth is made with silk (or linen) thread wrapped with very very thin gold strips. (Gold can be beaten into extremely thin sheets, and copper is not far behind.) – AlexP May 14 at 23:00
• Copper is one of the few elements that occurs naturally in its pure form. No metallurgy or smelting necessary. Find a nugget on the ground, just hammer away at it. it does not have to be processed or refined. Sort of like diamonds, or gold nuggets and flakes panned from streams. – Justin Thyme the Second May 15 at 3:33
• With the right chemicals, the patina on copper can be quite beautiful and dramatic. – Justin Thyme the Second May 15 at 3:40

# With enough effort, definitely

It's not just a matter of having enough copper. They also need resources, especially labor. Working copper into this format doesn't require very advanced technology and the ability has been shared by many cultures through history:

Copper was probably the first metal used by ancient cultures, and the oldest artefacts made with it date to the Neolithic period. The shiny red-brown metal was used for jewellery, tools, sculpture, bells, vessels, lamps, amulets, and death masks, amongst other things. So important was the metal in human development that it gave its name to the Copper Age, today better known as the Chalcolithic. (Source)

You need very thin sheets of copper to make clothing. Some of the Mississippian copper plates (replicas below) weren't that far away from what you'd need and they were made with a relatively low technology level.

The real challenge comes from crafting enough plates to clothe an entire population. If you have enough skilled people to run a large manufacturing operation, you could make it work.

• Copper was used because it was close to the surface, easily found and easily mined. Often, in the beginning, in pure form. Until the easy pickings were all exploited, of course. – Justin Thyme the Second May 15 at 3:27
• Would copper's tendency to work-harden (get stiffer the more it is flexed) be a problem? – evildemonic May 15 at 16:22

A "simple" method would be a single robe made of copper, rather than separate shirt-and-trousers.

In 2012, Indian businessman Datta Phuge commissioned a shirt made of gold. This took a team of 15 goldsmiths working for about 2 weeks to create! Since the Romans made both jewellery and chainmail, they should have the technology to do the same thing (although, not necessarily quite as fast)

This shirt weighed about 7.3lb / 3.32kg, so your "not too heavy" requirement might be in trouble - let's examine that.

If we assume that a robe would require approximately twice as much metal, then Gold would require about 14.6lb / 6.64kg. A "reasonable" backpack load for someone of Datta Phuge's size would be 12-18lb / 5.4-8.16kg

Gold has a density of $$19.32g/cm^3$$. Copper has a density of $$8.96g/cm^3$$. As such, making the robe from Copper instead of Gold would weigh 6.77lb / 3.08kg - this is lighter than the Gold shirt is, but still not something I'd look forwards to wearing all day!

However, beyond just the weight, I think that you would need to worry about chafing, and getting pinched between the links as they shifted around! Your citizens would probably want to wear undergarments made from a normal, more comfortable, fabric beneath their bling.

• "The shirt is crafted from 14,000 22-karat gold rings linked together and comes with six Swarovski crystal buttons and a belt also made of gold." –LA Times. So it's gold chain mail, not a shirt. Can you make copper chain mail with links that small and not have them glue themselves together after you start sweating? No, there's a reason other than pompousness that this was made out of gold: oxidation. – Mazura May 15 at 22:33

If you're prepared to let your civilisation discover a little chemistry/alchemy then it's possible to electrolessly (chemistry only, no electricity needed) plate metals such as copper onto fabrics such as silk (very fine woollen fabrics would probably work too). I don't know if it would work on cotton or other plant-based fabrics where the fibres are absorbent.

A similar fabric is available today, with copper plated onto nylon/polyester, and is used for electrical screening or earthing (for example in suits worn in Clean Rooms). I worked with this fabric back in the late 90's when I was working on wearable electronics (at Philips Research) and it comes off the roll looking just like fresh copper, with a beautiful peachy-orange glow, that then dulls down to a darker orange over time. The copper is on the surface of the fabric to ensure high conductivity so it'll also work for your anti-bacterial purposes.

Being plated, the copper layer is very thin and so won't survive a lot of polishing. Clothing made of it will gradually dull over time, though a quick dunk in some acid (nothing complicated needed, lemon juice will work) followed by a rinse in water would restore the shine, at least for the first few times.

I can't find a free to view reference on the plating process, so either use your favourite scientific paper downloader to get this paper: An alternative process for electroless copper plating on polyester fabric, or just look through the references, which are free, and see if you can find one that's available to download.

Given the age of technology, it does sound like they'd be familiar with metalworks and how to get the metal.
If they want to wear it like clothes, they'd need to find ways to refine to smaller sheets to keep it lightweight or turn it into a weave/wires that went with other fabric weaves as the clothes were made. This could be something they had learned more advanced than we did here given they had plenty of access to the abundance of ore.

Year's worth of metalwork could produce paper-thin plates that were near-weightless that could be sawn as panels onto a fabric shirt so the skin wouldn't get irritated. Skills would get passed down by tailors and metal-workers that's no doubt have a share in the business.

How they're made...they would no doubt melt down the ore into smaller, flatter shapes for specific things, like a circle or square and use a hammer to thin it out, as a blacksmith would do. Casts and molds wouldn't be too hard for a starting point.

• They did know how to make very thin wire in ancient Rome, and they did know how to weave gold and silver. Copper works in exactly the same way, it is just about as ductile. – AlexP May 14 at 21:01

If sufficiently pure and/or frequently annealed, metal wire can be knitted or crocheted. Arline Fisch is particularly adept at this. Here is a glove woven from fine copper and silver wire: https://americanart.si.edu/artwork/bracelet-and-glove-71852