Fuchsite is a green variety of muscovite mica. It differs from most other muscovite by having a variable amount of trivalent chromium substituting for aluminium within the mineral. Chromium is the source of fuchsite’s green color. Muscovite begins to take on a very light green color with the substitution of a small amount of chromium for aluminium. As the amount of chromium increases, the green colour becomes stronger and ranges to a rich emerald green when abundant chromium is present. The chemical formulae of muscovite and fuchsite are shown in the table. Fuchsite is found in phyllites and schists in metamorphic rocks of the greenschist facies. In most instances it occurs as tiny grains scattered through the rock mass, but occasionally rocks composed almost entirely of fuchsite are found. These green fuchsite-rich rocks are known as “verdite” - ""