Hureaulite


Hureaulite is a manganese phosphate with the formula Mn2+522·4H2O. It was discovered in 1825 and named in 1826 for the type locality, Les Hureaux, Saint-Sylvestre, Haute-Vienne, Limousin, France. It is sometimes written as huréaulite, but the IMA does not recommend this for English language text.
A complete series exists from lithiophilite, LiMn2+PO4 to triphylite, LiFe2+PO4, including hureaulite, strengite, FePO4·2H2O, stewartite, Mn2+Fe3+22·8H2O, and sicklerite, PO4.

Environment

Hureaulite is a secondary mineral occurring in granite pegmatites. At the type locality it occurs in a zone of altered triphylite, LiMn2+PO4, in pegmatite. Typically occurs very late in the sequence of formation of secondary phosphate minerals. Associated at the type locality with vivianite, Fe2+32·8H2O; rockbridgeite, Fe2+Fe3+435; heterosite, PO4 and cacoxenite, Fe3+24AlO61712·17H2O. It can be synthesised; most natural hureaulites are Mn-rich compounds but extensive solution is known for synthetic material.

Localities

The type locality is Les Hureaux, Saint-Sylvestre, Haute-Vienne, Limousin, France. Hureaulite is also found in a granite pegmatite known for its phosphates in the Aimorés pegmatite district, at the Cigana claim in Galiléia, Doce valley, Minas Gerais, Brazil, formerly known as the Jocão Mine.