Real gold versus fool's gold and mica: a practical field guide

Pyrite and mica are the two materials that fool new panners the most, and both can be ruled out with simple field tests rather than guessing from color alone. Malleability is the fastest test, press a flake between two hard surfaces or tap it gently with the back of a knife. Real gold flattens and deforms without breaking. Pyrite is brittle and will shatter or crumble into smaller pieces. Mica flakes apart into thin, flexible sheets and is unmistakably lightweight once you have handled real gold for comparison. Color is a secondary clue, gold keeps a consistent, buttery yellow color from every angle as you turn it in a pan, while pyrite often shows a slightly brassier tone and sometimes small cubic crystal faces, and can develop a faint iridescent tarnish. If you want a conclusive answer rather than a guess, specific gravity is the test that actually settles it, gold is roughly four times denser than pyrite, which is also why gold concentrates so efficiently at the bottom of a pan while pyrite and mica wash away with the lighter material.