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Recovering gold from investment powder paste

February 27, 2010

hi,
my name is Shakeel, I am for Bahrain. my father has recently started making 21k jewelry by the casting process.

we are worried as we have been losing on an average 3-4 grams of gold per KG whenever we cast, we use the wax melting process.

we have experimented with the investment powder left over but have not been able to recover anything.

PLEASE suggest help us in recovering this gold. we are a small workshop with limited resources. please advice a formula which we can use to extra the gold from the investment powder's paste.

we will be much obliged. Thank you.

warm regards

Shakeel Amjad
gold smith - Bahrain

I seem to remember an excellent article on the recovery of precious metals from used casting investment somewhere on the internet. I believe the author's name was Schneller. If I remember right, he first concentrated most of the PMs in about 5-10% of the investment material by a simple screening process.

Chris Owen
- Nevada, Missouri, USA
March 6, 2010

Hi Shakeel, I am working as gold refining officer in jewelry, Mumbai. You will not get any gold in investment powder.if you have any doubt, you dissolve this powder in hydrogen peroxide in plastic jar or you evaluate your loss against pure gold. or if you have more loss, then check your alloy percentage composition for any volatile metals like zn, cd, indium,silicon etc.

Bhupesh Mulik
- Mumbai
March 13, 2010

thank for your help.

Shakeel Amjad
- Bahrain
November 17, 2011