REDDINGITE

    Class : Phosphates, arsenates, vanadates
    Subclass : Hydrated phosphates
    Crystal system : Orthorhombic
    Chemistry : Mn3(PO4)2 3H2O
    Rarity : Rare to very rare

Reddingite is a secondary phosphate of granitic pegmatites, in which it forms by alteration of primary phosphates, usually triphylite or lithiophilite. Its name comes from its place of discovery : Redding in Connecticut (USA). Reddingite is usually massive, rarely in small pseudo-octahedral crystals, sometimes tabular, usually grouped in parallel aggregates. It is colorless or weakly tinted pale pink or pale yellow-brown; it becomes orange-brown by oxidation.

Main photo : Reddingite from Hagendorf pegmatites, Germany © Christophe Boutry

Reddingite in the World

It is a rare phosphate that has been found mainly in the pegmatites of Maine (Buckfield, Greenwood districts...) and Connecticut (Branchville). It is also known in the Hagendorf pegmatite (Germany) which produced the largest known crystals (8 mm), and in Brazilian pegmatites from Galileia in Minas Gerais (Brazil) and measure 3 mm.

Reddingite in France

Reddingite is not present in the French underground.

Twinning

No known twinning for this mineral species.

Fakes and treatments

No fakes listed for this mineral species.


Hardness : 3.5
Density : 3 to 3.2
Fracture : Irregular
Streak : White

TP : Translucent to transparent
RI : 1.643 to 1.685
Birefringence : 0.031
Optical character : Biaxial +
Pleochroism : Visible
Fluorescence : None

Solubility : Acids

Magnetism : NoneRadioactivity : None