Very interesting, but I'm afraid I have no clue what this is.
Perhaps we could all chip in a dollar to help you purchase this. You could try it out and report back to us.
Regards
Bob
The guy that is selling the stuff and claiming it is safe is --deleted--, and liable for a lawsuit when someone kills them self trying to recover some gold that way. Anytime you roast/heat up black sands without proper ventilation you run the risk of breathing in lead/mercury/arsenic and other dangerous metals/chemicals. Just make a miller table for 40 bucks and recover the gold that way...
Why I am saying it is dangerous, is the guy is advertising that it is safe cooking black sands on the stove at home, using that method. Sure, the bismuth or w/e it is might be safe to heat up that way, but for most blacksands, that's probably not a good idea without proper ventilation. Just reading that reminds me of that guy that cooked off his mercury in the trailer stove and killed himself and his family.
My little prototype had way too much drop to work right (though it did work well enough to catch those specs), but others posted some great examples. I have a full table about 95% done now, just need to attach the pump.