Gold panning. Historical engraving of workers in a mine using a large sieve to pan for gold. Material excavated from the mine is carried in a wheelbarrow to the sieve, which has water running into it from a man-made channel. The lighter stones and rocks fall through the sieve and are washed away. The heavier gold ores are left behind in the sieve. Taken from The Laws of Art and Nature, in Knowing, Judging, Assaying, Fining, Refining and Inlarging the Bodies of Confin'd Metals (1683) John Pettus, a translation of the book by Lazarus Erckern.