Kentrolite - Encyclopedia
Class : Silicates
Subclass : Sorosilicates
Crystal system : Orthorhombic
Chemistry : Pb2Mn2O2Si2O7
Rarity : Rare
Kentrolite is a rare lead and manganese silicate present as a very accessory mineral in metamorphic manganese deposits. It forms a series with melanotekite, its iron-bearing equivalent. Its name comes from the Greek kentron (point, thorn) because its prismatic crystals form thorny agglomerates. Kentrolite is a very dark reddish-brown mineral, almost black, which produces small, short prismatic crystals often grouped in sheaves.
Main photo : Kentrolite from Big Chief Mine, New-Mexico, USA © Jerry Cone
Kentrolite in the World
Twinning
No twin known for this mineral species.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 5
Density : 6.26
Fracture : Irregular
Streak : Brown
TP : Translucent
RI : 2.100 à 2.310
Birefringence : 0.210
Optical character : Biaxial +
Pleochroism : Strong
Fluorescence : None
Solubility : Hydrochloric acid
Magnetism : NoneRadioactivity : None