Generaatorite

Generaatorite is a rare phosphate mineral that forms small, elongated crystals in hydrothermal veins. It was first described in 1992 from the Larin Ridge deposit. The name derives from the word generator, reflecting the discoverers’ idea that the mineral may be involved in geochemical energy processes. The International Mineralogical Association recognizes generaatorite as a distinct species.

Chemistry and structure: The ideal formula is Na2Ca3Fe2(PO4)6, with partial substitutions of Na by K and Fe by Mn reported in nature. Generaatorite crystallizes in the hexagonal system and usually forms tabular to prismatic crystals. Its structure features a three-dimensional phosphate framework with calcium- and iron-rich sites.

Physical properties: It is pale yellow to olive-green, with a vitreous to pearly luster and a white to pale-yellow streak. Mohs hardness is 5–6; specific gravity is about 3.5–3.8. Cleavage is imperfect and fracture is uneven.

Occurrence and formation: Generaatorite occurs in hydrothermal marble-hosted veins within ultramafic rocks and is commonly associated with magnetite, titanite, and apatite. It forms at moderate temperatures under reducing conditions.

Significance and use: The mineral attracts interest for crystallography and substitution chemistry. It has no known economic value and is not an ore.