refining gold plated and gold filled jewlery

[hiscomm]

Hi:

started with about 200 grams of gold plated and supposed gold filled junk jewerly off of ebay. I decided to melt it in a induction furnace into shot, to possibly give me some more surface area. I then proceeded with a nitric bath for about 3 hours on a hot plate in a fume cabinet. After about 24 hrs I decanted off the acid and started 3-4 distilled washings. A whole lotta of what looked like rust was in the bottom of the chemical cup. Once I got all that cleared out I did another nitric bath and then another 3-4 washings with distilled water. Finally started the AR and my liquid is not amber but a turqoise green. I tested with stannous and it tested positive for gold and as of this time I'm going to let it stand over night. My question did I waste my time melting it into shot and at this final chemical step should I still have that much impuities to cause my solution to go green on me after doing all the washings and two nitric baths?

I need some experiential insight on this

thanx

 

[joubjonn]

The only thing melting into shot is doing for you is creating more surface area. The metal would be the same as you started with. I place my gold filled jewelry straight into nitric. Plus you get to see how well plated your material is that way. The gold will retain its shape if the plating is thick.

 

[hiscomm]

The only thing melting into shot is doing for you is creating more surface area. The metal would be the same as you started with. I place my gold filled jewelry straight into nitric. Plus you get to see how well plated your material is that way. The gold will retain its shape if the plating is thick.

Do you ever see any rust formulation during your nitric bath?

 

[Westerngs]

The "rust" is the finely divided gold. I too would have skipped the shotting step.
The green is from copper and other base metals still in solution. I would continue, drop
the gold. I would then rinse the gold following Harold V's instructions. If you are lucky and careful,
you may still get 999 gold. If not, a second refine is in order.