Do metal loose weight after melting? Help

[jason77]

Hi im new to this forum and i hope i can find answers for this question
I sent 500 pennyweight of unused gold plated watch cases to a refinery. A day later he was trying to pay me for only 408 pennyweight. When asked why he said the material lost that weight 92 pennyweight after melting and that's normal HE said . Any information about weight loss of metal after melting please help

Is this true or the guys trying to scam me

 

[goldshark]

Do you know the thickness of each piece? Plating can vary, so it is hard for anybody to know the end result, until the end. If you sent to a reputable refiner, they are usually honest, as they want repeat business, not a bunch of bad mouthing. Gold does not evaporate at an appreciable rate, at normal melting temperatures. That being said, Gold plated is usually not thrown into a furnace, and melted into an alloy with the base metals included, but is usually chemically stripped of the Au first, or the base metals dissolved out first, depending on refiners decision of what the base metals are, and how they decide what is most cost efficient.

 

[Martijn]

Hi im new to this forum and i hope i can find answers for this question
I sent 500 pennyweight of unused gold plated watch cases to a refinery. A day later he was trying to pay me for only 408 pennyweight. When asked why he said the material lost that weight 92 pennyweight after melting and that's normal HE said . Any information about weight loss of metal after melting please help

Is this true or the guys trying to scam me

Was it only copper/brass/bronze base metal or was there any glass screens, plastic inserts, rubber seals and steel or iron parts in it springs, bushings, etc? Iron does not like to alloy with copper based cases and will go in the slag as sulfides. Part of the base metals will be absorbed in the slag as oxides.
For 750 grams of plated watches, you can expect about 1 to 4 grams of gold.

I think refineries have a discouragement policy when people are trying to send in tiny amounts that are hardly worth processing individually. They melt and sample analyze, and only refine when there is enough to fill a batch.
So unless you know exactly what was in your material, you wil never know if his claim is true or not.
It does not sound that strange to me.

Did you get paid on an actual assayed percentage or by the melt weight and a standard ' x dollars per kilo' price for plated material?