Prospecting Your Gold Placer Claim Last month we covered prospecting your claim with a metal detector. Detectors are inexpensive if you buy a used machine, and require no special BLM permits, bonds, etc. That method works fine if you have coarse gold or heavy concentrations of fines, flakes and pickers. Unfortunately, it does not work well if the area you are working has fines and flakes well disseminated in the sand and gravels that cover the bedrock where most of your gold