Phosphates, Arsenates, and Vanadates

Phosphates, Arsenates, and Vanadates

This mineral is characterized by its yellow-green color and strong fluorescence in UV light. An ore of uranium, its name comes from Autun, France. It is found in the oxidation zone of uranium bearing rocks including hydrothermal veins and granitic pegmatites.

Discovered in 1860, this mineral is named from the Greek word "to deceive" as it was often confused with other minerals. It is widely disseminated as an accessory constituent in all classes of rocks: igneous, sedimentary, and metamorphic. Fluorapatite is by far the most common species of this mineral group.

Occurs primarily in granite pegmatites of the lithium- and phosphate-rich type. Crystals may be enormous in size. Discovered in 1818, this mineral’s name comes from two Greek words meaning "blunt" and "angle," in allusion to the angle between the cleavages.

The dominant building block of this mineral class is the PO4- tetrahedron. Phosphorus, arsenic, and vanadium may substitute for each other within the tetrahedron.

The typical mineral is vitreous to dull, often strongly-colored, above average average in density, has an average hardness, and a low index of refraction. The minerals of this class can have very complex chemical relationships and structures. It is a large mineral class, but many members are rare.