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Anyone have any experience in figuring out a odd metal we keep finding in our cuppel? We have been assaying our cons from a lode mine. We take a 30 gram assay and once we have our lead button that goes to cuppel we end up with 16-20 grams of a very heavy gray/silver button. For it's size it is as dense as gold it can't be silver. The ore comes from the sulfide level but is not a sulfide. It does not roast off and under a microscope its a silver/metal. Wish I had a xrf and that would be the end of it.

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Try to sell some of it and the buyer will whip out an xrf and tell you what it is!

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The possibilities of what has gone wrong are so many in number that it is hard to say. Additionally, you've given so little information that I hardly even know where to start.

I don't know what kind of assay procedures you are using so that's a big question mark. I don't know if you are using a full oven fusion or some sort of torch type shortcut assay.

Your concentrates appear to be mostly sulfides and sulfides require a special different assay technique than your normal standard fire assay.

Are you adding a bunch of nails to the assay mix? The addition of nails to high sulfide assays is quite standard for the industry. The nails react with the sulfur.

Sulfides do melt and when they harden they form into a material that looks very much like a metal - even though it is not. Once melted, sulfides to not easily roast off because only the outer surface can react with any air. The other thing that goes with that is of course you need to get a lot of air to get any kind of roasting situation going.

I don't know that you are fully going through the cupelation process. What you have may be an alloy of lead with a little silver to harden it up.

What happens when you hit the mystery metal hard with a hammer? if you strike it hard and it's a melted sulfide, it will shatter. If it's some sort of metal it will mash down like lead.

I guess all I can say is if you can give us some more information and answer some of my questions above I may be able to offer you some help.

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Hit it with a hammer if it is brittle it is likley to be antinomy or bismuth.

If it is not brittle it could be if your lucky a pgm.

If it is hard enough to dent or mark tne hammer it is almost certainly a pgm.

Pgm= platinum palladium osmium rhodium iridium ect.

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Chris it's just a standard fire assay using a full electric oven. As far as sulfides we preroasted a batch for 2 hours and very little change or sulfur smell came out. That is when we put it under a high powered microscope and saw it more resembles metal compared to sulfides. No nails were used in assay. We double checked to make sure all lead was removed by recovering the metal in lead for a 2nd time using a new cuppel it only lost .1 grams from a 18+ gram button. The lead should of removed any impurities. When we hit it with a hammer it didn't shatter it more had a small dent.

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Pgm did come up a lot. Being realistic I don't see how it could be. We are getting about 30-40 pounds a ton of this stuff. Our assays are giving us over 50% medal. There is no way 20 pounds of platinum is coming from a ton of rock... Shenanigans!!!

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Do a sg test on it.

Weight in air then weight in water to figure out its sg.

If its any higher than sg18 its likley a pgm.

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