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Thick Triphylite Crystal on Matrix
PHOSPHATES; TRUE PHOSPHATES · ORTHORHOMBIC

Triphylite

Li(Fe2+)PO4 

Hardness
4–5
Streak
Colorless to pale gray
Spec. Gravity
3.3–3.6
System
Orthorhombic

About

Triphylite describes both a mineral series, as well as an individual mineral within the series. Triphylite is the iron-rich end member of the Triphylite series, and Lithiophilite is the manganese-rich end member. Minerals of the Triphylite series commonly alter to secondary phosphates such as Vivianite, as well as to manganese and iron oxides. 
Triphylite is named from the Greek words "tria", for threefold, and "phylon", family, alluding to it as being a mineral group with three cations (Fe, Li, and Mn).

Crystal Forms & Aggregates

Mostly in massive or compact form. Distinct crystals are uncommon, and they are usually tabular or prismatic with blocky form and many crystals faces. Cleavage fragments also exist, with distinct crystal faces within massive forms or rough crystals in matrix.

Striking Features

Environment

Uses

Triphylite has been mined as an ore of lithium.

Noteworthy Localities

Massive greenish-gray Triphylite was mined as an ore of lithium at Hagendorf Pegmatite, Waidhaus, Bavaria, Germany. Triphylite, often in altered form replaced by oxides, has come from the Assunção Mine, Ferreira de Aves, Sátão, Viseu District, Portugal.
In the U.S., the pegmatites of New England are the best producers of Triphylite, including those at New Hampshire, Connecticut, and Maine.The Chandlers Mill Quarry, Newport, Sullivan Co., New Hampshire, has produced large and visible crystals in the best examples of this mineral. Also in New Hampshire is the Palermo No. 1 Mine, Groton, Grafton Co., where Triphylite has been found in mostly massive forms, but also in occasional crystals. Massive Triphylite has also come from Keystone, Pennington Co., South Dakota.

Common Mineral Associations

Photos