General Information:
Chemical Formula:
Na3Sr4ThSi8(O,OH)24
Composition:
(Molecular Weight = 1,266.20 gm)
Sodium 5.45 % Na
Strontium 27.68 % Sr
Thorium 18.33 % Th
Silicon 17.74 % Si
Hydrogen 0.48 % H
Oxygen 30.33 % O
Empirical Formula:
Na3Sr4ThSi8O18(OH)6
Environment:
In ussingite veinlets cutting alkalic rocks.
IMA Status:
Approved IMA 1974
Locality:
Umbozero (Lake Umba), Kola Peninsula, Russia.
Name Origin:
Named for the locality.
Physical Properties:
Cleavage:
None
Color:
bottle green or greenish brown.
Density:
3.6
Habits:
Metamict - Mineral originally crystalline, now amorphous due to radiation damage., Pseudo Tetragonal - Crystals show a tetragonal shape.,
Hardness:
5 - Apatite
Luster:
Vitreous (Glassy)
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