Replies to post #115 on NMC Inc. (fka NMCX)

[echarter]

The only cases where lead fire assay will not detect atomically dispersed gold is where the contained minerals in the ore prevent the dissolution of the gold into the lead. Nickel sulphide causes matte to form on the button. Matte prevents the lead from collecting gold. Selenium will cause the gold to become more soluble in the slag than in the lead. Minerals which form better amalgams with silver than gold does can cause gold to not be collected well. Tellurides volatalize at low heats, and such ores do not give up their gold to lead with alacrity. There are ways around all these interferences with proper assay technique. Roast assays and high nitre assays can be employed. One mineral that often interferes without people knowing it is arsenoprite. Where gold is atomically bound to arsenopyrite, the gold may be more soluble in slag than in lead. Cold start roast assays should be employed here. Volatization losses have been found not to exceed 10%.

Kerr Addison Mine had about 15% of its gold atomically bound in pyrite. Atomic gold is as fine as it gets. These were not merely very very fine gold grains. They would not yield to 1000 mesh grind. Nevertheless this gold was assayable by fire assay. Butte Montana had fine gold locked up in quartz. Its size was below a micron in many cases. High grade too. Now a micron is far larger than an atom, I will admit, but far too small to be ground out of ore. Nevertheless, the gold was amenable to fire assay.

Atomic gold that is plentiful enough to mine can be seen by a scanning electron microscope. If it is there, it cannot hide. You may have to scan 200,000 or more atoms to find one gold atom, but it should show up. It could show up in backscatter techniques. This would solve the controversy, but I doubt that the company will try it. If there is an additional nugget effect it may take several tries. Scanning EM's do not cover much ground in one pass.

If the micro gold is in silicates you are screwed. You will not get it out with any economic process. I could do it at high grades, but I ain't tellin' them how. If it is in sulphides which is likely, you may get it out by roasting or autoclave. There should be no reason it should not go into solution despite the presence of arsenic.

EC<:-}