check collector value first, there just is not much(read tiny amount) of gold on them. If you can get 5 or 10 bucks for each you will be way ahead to sell them and buy some gold.
yeah, this plate is only worth 5 bucks on ebay. im just adding it to the mountain of other stuff i have with gold on it that im going start recovering after another month or so of collecting.
The gold will come right off in HCL/CL or AR but if the plate isn't chipped or broken, sell it!! You'll be way ahead, I only process broken china/glass ware, the rest I sell.