Manganese-bearing Fluorapatite

A variety of Fluorapatite

A high valence manganese-bearing variety of fluorapatite, generally containing Mn⁵⁺. The name "manganapatite" has been incorrectly applied to this variety.

When Mn²⁺ and, probably some divalent Fe, replaces Ca, the resulting colour may be dull green (McConnell, 1973). When Mn³⁺ is present, a pinkish or violet colouration results, which is typical for some alkaline pegmatites of the Lovozero massif. Some purple apatites have been studied by Mossbauer spectroscopy, and the purple colour has been ascribed to MnMn⁴⁺. Mn⁵⁺ can replace P and this will result in a blue colour (Johnson, Prener, and Kingsley, 1963; Hughes et al., 2004). For example, fluorapatite with high valence Mn⁵⁺ fluorapatite often forms blue rims around orange lithiophilite grains at the Rb-Ta Elash deposit.

NOTE: The names manganapatite or manganoan apatite have been used to describe certain samples of fluorapatite that contain divalent Mn that causes a golden-yellow fluorescent response under UV. Without the manganese, fluorapatite is frequently unresponsive to UV, although there are other fluorescence activators in the apatites. Large amounts of Mn in fluorapatite, generally > 4 weight percent, are poorly fluorescent to non-fluorescent.