Fred Stone said:
Does anybody have information on cupel losses in bullion assays for high selenium material. I have seen 100% loss on some material that is in the percent range for Se.
Selenium values over 2% seem to cause losses in cupellation. You should be able to remove some of the selenium in the crucible fusion with a high litharge flux (or perhaps in a scorification), but you may then have to correct for slag losses.
Perhaps a sulfuric pre-leach? Maybe a low temperature roast?
You will need to validate any method you decide on- especially if anyone is exchanging money :wink: .