Lithiophilite

Lithiophilite is a lithium manganese phosphate mineral with the chemical formula LiMnPO4. It is a member of the phosphate mineral class and represents the Mn-rich end member of the LiMPO4 solid solution series, which also includes triphylite, LiFePO4. Lithiophilite and its iron analogs form part of the triphylite group of phosphates, typically displaying an olivine-like structure in which lithium, manganese (or iron), phosphate, and oxygen are arranged in a framework.

Crystallography and appearance: Lithiophilite crystallizes in the orthorhombic system. In hand specimens it is usually found as small, prismatic crystals or as granular masses. In many pegmatites, crystals are rare and are commonly embedded in coexisting lithium-rich minerals such as spodumene, petalite, lepidolite, and amblygonite.

Occurrence and associations: The mineral occurs most notably in lithium-rich pegmatites and in some hydrothermal veins related to granitic rocks. It is frequently found together with other phosphates and lithium-bearing minerals, reflecting the geochemical conditions that concentrate lithium in pegmatitic systems.

Significance and nomenclature: Lithiophilite is not a major source of lithium but serves as an indicator mineral for lithium-rich pegmatites. The name derives from its lithium content; it is chemically and structurally related to triphylite, LiFePO4, forming part of the LiMPO4 phosphate family.

See also: Triphylite group; LiFePO4; pegmatite minerals.

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