Ungarettiite

General Information:
 Chemical Formula:
NaNa2(Mn++2Mn+++3)Si8O22O2
 Composition:
(Molecular Weight = 952.33 gm)
Sodium 7.24 % Na
Manganese 28.84 % Mn
Silicon 23.59 % Si
Oxygen 40.32 % O 
 Empirical Formula:
Na3Mn2+2Mn3+3Si8O24
 Environment:
Manganiferous silicate and oxide rocks.
 IMA Status:
Approved IMA
 Locality:
The abandoned Hoskins Manganese mine, 3 km west of Grenfell, New South Wales, Australia.
 Name Origin:
Named after Prof. Luciano Ungaretti (1942-), Universita de Pavia, Pavia, Italy.
Physical Properties:
 Cleavage:
[110] Perfect
 Color:
cherry red or very dark red.
 Density:
3.52
 Diaphaniety:
Transparent
 Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Granular - Generally occurs as anhedral to subhedral crystals in matrix.,
 Hardness:
6 - Orthoclase
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Adamantine
 Streak:
pale pinkish white
More details...