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
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