Fool's Gold can be one of three minerals. The most common mineral mistaken for gold is pyrite. Chalcopyrite may also appear gold-like, and weathered mica can mimic gold as well. Compared to actual gold, these minerals will flake, powder, or crumble when poked with a metal point, whereas gold will gouge or indent like soft lead. In addition, actual gold will leave a golden yellow streak when scraped on a piece of unglazed porcelain. Pyrite and chalcopyrite will leave a dark green to black streak and the common micas will leave a white streak.
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