Noxx said:
Thanks for all the great info.
You're welcome!
I'm currently building a tutorial on the subject.
That's nice------but it would serve the readers very best if it was good and proper information. There are tried and proven methods for standard refining that are easily accomplished----with no real reason for anyone to "re-invent" the wheel. There's a fair amount of misinformation being tossed around that is sure to create problems for some of these guys, or complicate what should be an easy process. Working with silver chloride is one in particular.
I'd suggest you do your research well, and choose a procedure that is in keeping with good practice. Lots of wives tales need to be abandoned so these guys can move forward with proper learning.
But note that my nuggets are +95% purity before I added them to the AR.
I'm curious how you know that. Properly refined gold should exceed 95% first time through, and have almost no silver. Rose suggests that a few atoms of silver will behave as gold and be difficult to eliminate, so a trace, at best, should show in once refined gold. Other base metals may differ, but they wouldn't prevent the dissolution of gold in AR.
After posting my comments, I read further and agree, the purple film you found was likely silver chloride, but it had obviously photo-reacted with sunlight. It's also possible for the gold chloride, absorbed by the silver chloride, to have done the same thing. Gold chloride, exposed to light, will leave purple stains on almost anything it touches Everything you described typifies what you would have experienced had it been silver chloride. The green coloration I spoke of would have been only if you had been working out of sunlight, and had not photo-reacted.
I assumed you were working indoors, in a fume hood, ---but realize most of these guys don't have that luxury.
Maybe the one who did not dissolved had a surface layer I don't know...
I have serious reservations about a "surface layer", aside from one forming from residues that accumulate (like silver chloride).
I will try to «corn flake» it lol :lol:
They work great. By the time the insoluble layer has formed, the entire lot is usually dissolved, so the silver chloride just crumbles and turns white----and all the gold goes into solution. You may wish to look for some tiny bits that don't fully dissolve, for occasionally one of the flakes will have a heavy cross section. This process works very best if you use it for the preliminary operation, where you remove base metals via the inquartation/nitric process.
The process of making the corn flakes is simple. Have a deep container (metal----never plastic), at least the size of a 5 gallon bucket. A grease can, one you might see in a place like Jiffy-Lube (about 20 gallons in size) would work great, but should be well cleaned if used). Fill the container with cold water, then melt your button with a torch. Pour the molten metal into the water filled container in a thin stream, moving around the container so you don't get an accumulation of hot metal in one place. It can fuse to the container if you don't have enough depth, or poor too much in one place at one time.
You don't get shot when you perform this operation, you get, instead, flakes, best described as corn flakes, thus the name I applied.
If you need to talk about the inquartation process, ask. It's fairly critical, in order to get the base metals out without breaking down the gold into fine powder. Hoke's book covers it perfectly, which is one of the reasons I keep telling you guys to buy the book. It also teaches you how to test metals.
Harold
I don't have any at hand, I only have jewelry that is +14kt so Nitric Acid can't dissolve it...
