Melanotekite - Encyclopedia
Class : Silicates
Subclass : Sorosilicates
Crystal system : Orthorhombic
Chemistry : Pb2Fe2O2Si2O7
Rarity : Rare
Melanotekite is a rare lead and iron silicate present as a very accessory mineral in metamorphic manganese deposits and lead hydrothermal deposits. It forms a series with kentrolite, its manganiferous equivalent. Its name comes from the Greek melanos (black) and têktos (melted) to emphasize the fact that the mineral heated with a blowtorch melts, forming a blackish mass. Melanotekite is a black to blackish gray and blackish green mineral, which gives small spherules or irregular masses, rarely small pointed crystals.
Main photo : Melanotekite from Tsumeb, Namibia © Carsten Slotta
Melanotekite in the World
Twinning
No twin known for this mineral species.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 6.5
Density : 5.73 to 6.28
Fracture : Undetermined
Streak : Grey-black
TP : Translucent to opaque
RI : 2.120 to 2.310
Birefringence : 0.190
Optical character : Biaxial +
Pleochroism : Visible
Fluorescence : None
Solubility : Nitric acid
Magnetism : NoneRadioactivity : None