Starmex 
On platters the foil is nickel the base metal is aluminum. I dont see anyone making any money on platters. Best case sceneario there worth 90 cents per pound. I have seen people buying them at $2 per pound so i have no idea where the extra value is coming from. I think the platinum you are referring to is only 30nm thick layer which is basically nothing, like 10 cents worth per platter at most, providing it could be recovered in an economical way which it cant at that concentration.
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