Smelting Gold ore Attempt

[00:00:00]It's time for the smelting project. Now, a while back I did a video where our friend Dave gave uh me some ore from his gold mine in Montana. Well, I crushed it all up and tried to get the gold out, but it was so fine and actually pretty difficult to extract the gold. And the ore looks to be pretty sulfide rich. So, I think there's still a lot of gold left in here, and I think smelting might be a good way to get it out. Now, common misconception, there is a difference between smelting and melting. People go off in their garage and melt aluminum cans and they say, "I'm going to go smelt some aluminum."

[00:00:36]No, you're not. You're going to melt the aluminum. Or they take copper wire and they're like, "I'm going to go smelt some copper." No, you're not.

[00:00:44]You're going to melt the copper. The difference is this has already been smelted and refined. Smelting is a chemical process to extract the elements out of the ore. Unless you have a piece of native copper like this, you got to smelt it. So, common ore for copper is azurite and malachite. It's a copper carbonate. So, you have to strip off all those carbonate atoms, burn those away, get those to chemically separate in order to get pure copper. Same with iron oxide, you got to strip off the oxygens to leave pure iron. If I were to simply try to melt this, I would end up with a glassy material like volcanic glass, and I wouldn't be able to extract any of the minerals out of it. It'd just be locked up in a glassy mess. That's where the chemistry comes in. So, we're going to get to smelting today. Now, I've dried out a sample of it.

[00:01:38]Now, I've dried out a sample of it and I have 600 g right here. My recipe comes directly from Jason from Mount Baker Mining and Metals. He's probably got the most extensive collection of smelting videos out there. And he can explain the chemistry better than I can. As far as materials, I went to a pottery store and I bought the materials directly from them. So, I got borax. I'm not sure if it's anhydrous borax. That makes a difference. Some borax can have water in there and if you heat that up, it'll like steam off. It releases the water.

[00:02:08]Doesn't say it's anhydrous. I would think from a pottery store it might be, but we'll find out. Got some silica sand and this is the form of flint, which is like a form of chert. It's still silicon dioxide. It's not really silica sand, but I would imagine it would work the same. Chemically, it's the same. Got my soda ash and bismuth trioxide. Dave also gave me this from his shaker table. It's concentrates from a shaker table and I'm going to test that, but I'm going to go through a test run here first just to shake out all the kinks and we'll get to this at a later date. I quickly realized I wasn't going to have enough soda ash.

[00:02:43]I don't know why I bought this baby bag.

[00:02:45]So, I went out and bought a 25 lb box.

[00:02:49]This cost $37. If you can't tell, I've got several smelting projects I want to do. Anyway, I have weighed out 600 g of soda ash and I'll add that to our ore, I guess.

[00:03:09]Look at this. I dumped it all into a quick trip buddy cup and it stratified as I did. You can see all the layers that form there. All it takes is moving sediment and a density differential and you can get layers like that. There are many different types of strata, though.

[00:03:24]The next up is the flint.

[00:03:26]Hold on. That's rounded. That's not flint.

[00:03:30]That is rounded beach sand. Looks like the St. Peter Sandstone.

[00:03:35]Okay. Silicon dioxide, but I'm calling BS that that's flint.

[00:03:40]Flint forms a different way. It's not the same thing. It's fine. This is what I wanted anyway. I might be mixing up too big a batch. That borax is exceeding my quick trip buddy cup.

[00:03:52]But, I went into my wife's kitchen and found this cool cake pan. That'll hold everything I need. Last thing is a bismuth trioxide. Don't remember what this cost, but 1 lb was that much.

[00:04:05]For this batch, I need 180 g. That is more than I hoped that would be.

[00:04:11]That's what 180 g looks like.

[00:04:15]Doesn't that look scrumptious? Just need to make sure I can wipe all the sand out of there before I put it back in the kitchen. I'm going to test and see if it'll all fit in my crucible here.

[00:04:31]I'm only going to fit about half of it.

[00:04:38]Yeah, that's not even close to big enough.

[00:04:42]Well, now we know. Doesn't even look like ore anymore.

[00:04:47]So much other stuff.

[00:04:49]I'm going to fill this to just over half full because as all that's heating up, it's going to be gassing off different gases.

[00:04:57]So, bubbles and froths and it expands.

[00:04:59]So, it can really easily overflow your crucible. That's what Jason of Mount Baker Mining and Metals always says. So, I'm going to take that advice. We'll just start going and see what happens.

[00:05:08]So, looks like my crucible's going to fit less than half of what I mixed up.

[00:05:13]Mhm.

[00:05:28]I'm going to heat that up slowly and kind of monitor it because if it does start to really start to degas quickly, I want to be able to keep an eye on it.

[00:05:37]Now, I designed these furnaces to have a good vortex in there because that helps heat the metal when I'm melting bronze and aluminum and whatever. But, it looked like it was disturbing that loose flux too much. So, I'm going to let it heat up with the lid off. Maybe it'll heat up enough to kind of start to melt together and then it won't blow away with the the vortex of the furnace. Also going to try to stay away from any fumes because I don't know the mineralogy there and you can get arsenopyrite so there can be arsenic along with the sulfides.

[00:06:06]So, there could be kind of toxic gases coming off of that or lead sulfides or you know, just a lot of things.

[00:06:12]Basically, don't breathe what comes off of that.

[00:06:22]You could see it was expanding quite a bit and then it got to a point where I put the lid back on and it was like all sticky. It just kind of glopped together.

[00:06:31]So, that's good. But now I think the expansion is at its maximum point. It's starting to go back down. So, I'm wondering if I can just put more in there now that there's more room. So, I'm going to cut off the air flow.

[00:06:44]Here's what I'm going to try. I'm going to try putting this in there cold. Just see how much I can get in there now that it's done expanding. That is back to full.

[00:07:01]Yeah, I mean it looks like that worked.

[00:07:03]So, I can do a little bit more than I thought.

[00:07:12]Now, I need to add some nails to help with the chemical reactions. I believe it's a sulfides that bond with the iron in the nails. So, after everything is freed and locked up, I need to consume some of the freed up ions by putting nails in there. I re-roofed my house. I have a bunch of scrap nails that I picked up. Hopefully, they'll work.

[00:07:37]It's reduced so much. I'm actually going to try to put more in there.

[00:07:48]I don't see a reason not to.

[00:07:54]I actually fitted all in there. Didn't expect that. All right, all the bubbling has stopped, so I'm assuming that means the chemical reaction is done. Let's pour it.

[00:08:23]That's so cool. It's literal lava coming out of there. Now, hopefully there's a molten bead of bismuth down there full of gold. I'm just going to let that sit overnight and I'll come back to it in the morning. Okay, that's completely solidified. You can see kind of depressed there where it shrunk and contracted. You can see the nails here.

[00:08:41]They don't look super corroded, so I hope they were the right kind of metal. Let's flip it over and see if we got a button.

[00:08:49]Oh boy.

[00:08:50]Just fell right out.

[00:08:54]Oh, man.

[00:08:57]It's nothing but glass.

[00:09:03]There's no metal button at all.

[00:09:07]Why?

[00:09:09]There appears to be some metallic shimmer to it, but it's not like separated. And inside there are some inclusions of what looks to be unmelted material. So, I don't know why it didn't work, but all the material is still here, so I'll I think the only thing to do now is to remelt it. Just try it again, let it sit for a little bit longer. Maybe it needed more time. Maybe it needed to be hotter.

[00:09:34]So, I'm going to do both those things, try it again, and see if I can get the metal button to drop to the bottom.

[00:09:51]So, this is back up to temperature and it's actually boiling again. So, I think the first time maybe I didn't have it hot enough. Looks better than the first time, so I'm just going to pour it again.

[00:10:23]Now, I don't know why the crucible has that white smoke coming out of it. The white smoke is usually a sign of like the burning off sulfides. If it's sulfides, why is it burning off now when it's exposed to the open air? It also looks a little bit different from when Jason from Mount Baker Mining and Metals does it because his seems to like glow more and like royal more after he pours it into his uh mold. So, I feel like he's getting it hotter than I'm getting it. I'm getting it pretty hot. I mean, that furnace melts copper, no problem, so it should be hot enough. We'll just see what it looks like. I'll let it cool a good long while.

[00:11:02]All right, so that's cooled down and this one cracked a little bit more when it cooled.

[00:11:07]I don't know if that means anything.

[00:11:10]Kind of interesting. Still a little bit hot. I really hope there's a metal bead at the end of this one.

[00:11:20]Gosh, that really does come to a fine point.

[00:11:25]Doesn't look like metal, though.

[00:11:27]Ooh.

[00:11:28]Ha ha ha. I I it worked a little better that time.

[00:11:32]I see metal in there.

[00:11:38]>> [applause] >> I think it was successful. I'll try to chip all that glass off of there, but I think that's what we were looking for.

[00:11:44]Sweet.

[00:11:48]And that is a horrible recovery. So, more than half of our bismuth oxide did not come to the bottom. I would assume it's still in that glass. Definitely still got a lot to learn about smelting.

[00:12:00]So, now I've got my cupel, and when I put the prill in there, I'm not sure it's all going to fit. It's going to be close, but I really don't want this to overflow. I might break it in half and try two, or I might risk it. I'm not sure yet.

[00:12:13]These cupels looked bigger in the picture.

[00:12:16]They're a lot smaller than I thought they'd be. But, somehow when this heats up, it's supposed to oxidize and disappear into the cupel. All the bismuth will oxidize and disappear, but any gold or silver left behind should stay in a little bead in there.

[00:12:33]At least that's how it happens on TV.

[00:12:35]And I got my electric kiln there, and that should do the job just fine. I'm going to let that cupel heat up, and I'm going to slowly put this in there. It should melt basically on contact. And if it looks like it's going to overflow, I'll just take it out and put it in the next one.

[00:12:56]Oh, that'll be fine.

[00:13:01]Sweet. That'll fit the metal, no problem.

[00:13:04]Now, how long do I let it sit there?

[00:13:10]I don't know. It's 10:15 right now.

[00:13:13]We'll just check on it later and see what it looks like.

[00:13:22]Look at this odd piece that won't melt.

[00:13:29]Is it those are iron.

[00:13:37]Holy crap, they're pieces of iron.

[00:13:40]Why?

[00:13:42]So, somehow there ended up to be several pieces of iron floating in my prill. I know I didn't have the furnace hot enough to melt iron, but iron can dissolve into other metals. I just don't know why this would have dissolved.

[00:13:55]I don't know why it would form a bead like that. I don't know if it came from the black sands or if it came from the nails I put in there. I've never seen that happen on Mount Baker Mining and Metals.

[00:14:18]Okay, it's been about 2 hours that it's been in there, and there's a point where it goes from liquid to solid because it's above the melting point of the bismuth, but it's not above the melting point of gold or silver. It doesn't have to be above the melting point for those minerals to be molten.

[00:14:35]Just like when you put salt in the water, the salt will dissolve into the water, but it's not above the melting point of the salt. Same thing with metals. The metals can actually dissolve into other metals, but as that bismuth gets driven off, eventually the gold and silver will get so concentrated that it will revert back to a solid, and that's what I'm hoping is in there, a little bead.

[00:14:59]A little bead of solid gold.

[00:15:01]Ooh, there is a tiny little bead. That is really cool. Look at that.

[00:15:08]Isn't that something? Now, where did all the other metal go? Did it go in the air? Is it in that cupel?

[00:15:14]I don't really know. I just know it's pretty cool. You can see it is a solid bead.

[00:15:22]All right, let's see if this registers on the scale at all.

[00:15:31].022.

[00:15:32]There's even a few gold specs left in there to compare color.

[00:15:36]It's pretty silvery. So, I think we got mostly silver, but I'm sure it's a mix of both. So, based on that weight, I'm not sure we really got the best recovery.

[00:15:47]I'm going to have to learn a little bit more about this, but it did kind of work. So, proof of concept, we can do it. We just have to get better at it.

[00:15:54]And by the looks of this, it's very silvery. So, I think there's a high silver content, which should be honest, is kind of typical for a lot of gold mines. But, how cool is that? We did it.

[00:16:04]We smelted and cupelled, and we got a little bead of looks like silver. And I'm sure there's gold in there. I just don't know what the ratio is. Super cool. We're going to keep doing experiments with that. So, I hope you enjoyed watching this. Come on back for the next one. Bye-bye.