Gravitational Method
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Gravitational attraction is not constant on Earth, but depends on the density of the rock underneath the object as well as it's distance from one pole or the other. Because density of groundmass can effect gravitational readings, minerals with a high specific gravity concentrated in a large enough quantity can be detected with a gravity meter.
Minerals with a high specific gravity include Au, Pb, and Pt.
Minerals with a high specific gravity include Au, Pb, and Pt.