Okay, I have an idea or two. For full disclosure I work for a
refiner, and I’m about to suggest you have your metal actually
refined. LOL. So despite my monetary interest in refining-We have
always done “same molecule” refining at PMWest. But I can offer one
real experience that shows whats up. We used (15 years ago or more)
to refine for a then famous California mine that had its own retail
jewelry line sold in California gold country stores. Between several
contract casters, finishers etc, and the mines best efforts at every
flux imaginable, the metal had to be fully refined before it was used
for very fine jewelry sold to picky customers. High karat = high end
= picky customers. This customer insisted it all be “their” gold from
their mine for obvious reasons.
We did chemical analysis to determine what was in the alluvial
placer gold. Gold, copper, silver and /junk/. We then re alloyed with
all but the junk, added gold copper and silver in proportion to make
up for the 1% or so of real junk materials. The final product worked
really well. Some of the junk will embrittle gold very badly.
Ever notice how alloy makers can add a tiny bit of something and
improve the properties a lot? Unfortunately it happens in reverse
too. Very small amounts of junk can ruin the workability or final
finish. In the end the 22kt+ jewelry had the very same gold, and the
very same look as the nugget and dust gold.
Daniel Ballard