Black precipitate

[Riyoso]

I dissolve all kinds of CPU scrap with a high content of copper, other metals and gold in AR solution. Then boiling down solution 3 to 4 times to eliminate nitric acid.I then precipitate with smb abit more then needed i get a black precipitate that i clean with all the steps needed but when melting precipitate it usaly comes out silver is it possible to desolve precipitate in nitric acid only to get clean gold or is there any other way of cleaning this precipitate?

 

[butcher]

if you just added nitric to your precipitate the chloride salts will disolve some gold, you should always, incenerate, between acids, suggest you do a seach for Harolds posts, he has explained it so well and a little reading is worth more than the gold you have.

 

[Lino1406]

There is gold there, you can boyl
in sulphuric acid 20% which dissolves
silver to some extent (and copper and iron)