Starting over by precipitating with Lye

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I received a bottle of waste acid from a person who tried to recover gold from various sources but could never quite get it right. I precipitated all the metals using lye (Sodium Hydroxide). I filtered and dried, leaving myself with a powder of various metals. Do I need to melt back into a metal or can I start stripping out the metals with the powder?

My method to remove non precious metals will be the following
1) Boiling hydrochloric acid with distilled water- filter out remains for next step
2) Boiling nitric acid with distilled water- filter out remains for next step

Finally recover gold with Aqua Regia

 

[orvi]

What you did is precipitation of metal hydroxides, not metals. This is not particulary good approach to selectively stripp the gold from it.
If you try to melt this pile down, only with suitable reducing agent to convert the hydroxides to metals - and this is known as smelting.
Adding hydrochloric acid will probably get you where you started - you dissolve practically everything...

I would dissolve what could be dissolved again in HCl with some minute HNO3 to get everything into the solution, then precipitate the gold with reducing agent like sulfite or ascorbic acid.