HCL and Black Sediment Concerns

Gold Refining Forum

Help Support Gold Refining Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

AlphaBaby

Member
Joined
Mar 29, 2019
Messages
7
Hi everyone. I have a batch of HCL and Peroxide used on gold plated jewelry material and I have gold with a black powder forming in the bottom. I'm not sure if it's silver chloride or something else forming. I took a small sample and tried dissolving with nitric acid after washing five times with distilled water and it seemed to dissolve some and cement some other parts in the bottom with the gold remaining. I was also able to melt a small portion and it is a silver color metal but very brittle when hit with a hammer. I did a silver acid test on the small metal melted piece and the acid was coming back light blue. I did a small aqua regia batch with this same stuff in it and it remained a grey sludge in the bottom of the beaker. Any ideas as what this may be or how to recover the gold properly? Thanks everyone for any help with this topic. - Matt
 
"If the "silver acid test" was Schwerter's solution, a red solution, it's probably nickel. See beware of this ebay seller!."

I learned a lot from that post on a number of levels. Thanks for providing the link Dave!

Sent from my LG-H872 using Tapatalk

 
Maybe they are gold. As you know, When gold dissolves in AP, It precipitate as black powder
 
Hi all, I'm a newbie to the forum, an to of gold recovery and refining however I been doing all kinds of reading and watching of YouTube trying to figure out an efficient way to process scrap so I have decided to go with peroxide acid to dissolve cpu pins and mlcc at first I made the first batch into the scrap and it made a greenish murky sludge around the material then I decide to make a new batch of ap to start over again I then add the contents of the first batch an it immediately turned murky red what kind of reaction is this having is it attaching to the copper ion that are giving the ap its color and if so what am I to do to separate bms(base metals) an precious metals out of each other should filtrate ap and use a different solution instead of AP since it's only good for certain metals. Any info for this process is greatly appreciated.
 
Back
Top