When I lived in Arizona I did an excessive amount of rock hounding. I actually have quite an extensive rock and mineral collection in my home. I have around 50 pounds of stone with copper in it. It looks really cool in the rough. I recently decided that I’d love to smelt some of it, to extract the copper with in.
How do I do this?
I have a blow torch, but I do not think this is the best method of extraction. Additionally, what type of receptical should I use to catch all the copper coming out…granted, I’m picturing it flowing out of the stone…I’m probably wrong. So what do I need?
I believe that the traditional method of smelting copper involves heating the ore to a high temperature in a charcoal furnace; it is possible that undesirable elements such as arsenic may be present in the ore and that you could inadvertently expose yourself to poisoning.
(Other possible Cu ores–I forgot the sulfides(!): chalcopyrite, bornite, chalcocite, covellite. These sulfides require more energy to smelt (i.e., break the Cu-S bonds) than do the oxides, carbonates, and phosphates I listed previously.)
The copper is in various rocks, but most look like this . I have one large specimen that weighs probably 5 pounds and is mostly copper. They all came from the Globe area of Arizona, roughly 30 miles east of Phoenix. Right in the middle of copper and turquoise mine country.
I would suggest that you google some of the archeo metallurgy sites. There are some strong groups in europe. I have seen it done. Generally, you would need some type of furnace (clay). The furnace is loaded with alternating charcoal and cupric ores layers. The fire is started from below and air is fed through tuyeres below (historically, these are tubes that stick into the bottom of the furnace and air is supplied by inflating and compressing skins). A lot of work for the little bit of copper. You could also use some type of propane and a blower system. charcoal is better fuel source.
It sounds like you are describing the smelting of iron and not copper. Copper is much easier to deal with as it has a lower (500[sup]o[/sup] lower) boiling point. The question for Phlosphr what do you want make with the copper (ingots or just lumps) and how pure do you want it to be?
i saw someone on TV, on an archeoology program get copper by putting malachite in a regular wood fire outside. They were demonstrating some of the earliest techniques for getting metal from ore.
Apparently, some people have found out how to smelt common metals in a microwave. I’m not sure if it was hot enough for copper, I think pig iron was okay.
Actually, not really. The entire thing consists of some kind of ceramic outer layer filled with little pebbles of something or other that were REALLY good at absorbing microwave energy. Pack in some metal shaving and the entire thing gets very hot without damaging the microwave. The metal never gets directly heated, it just comes in contact with the pebble things.