General Information:
Chemical Formula:
Th(Ca,Na)2(K1-x,[ ]x)Si8O20·n(H2O)
Environment:
Found in the albitized exocontact zone at the Djelisu and Dara-Pioz alkaline complexes. The calcium dominant analog of steacyite.
IMA Status:
Approved IMA 1996, (Dana # Added)
Locality:
Located 40 km apart north and south, respectively, of the Turkestan - Tadjikistan border.
Name Origin:
Named after the discovery locality, along the Turkestan Ridge.
Physical Properties:
Cleavage:
[111] Imperfect, [111] Imperfect, [111] Imperfect
Color:
apple green, dark green, or brown.
Density:
3.36
Diaphaniety:
Transparent
Habits:
Granular - Generally occurs as anhedral to subhedral crystals in matrix., Euhedral Crystals - Occurs as well-formed crystals showing good external form.,
Hardness:
5.5-6 - Knife Blade-Orthoclase
Luminescence:
Non-fluorescent.
Luster:
Vitreous (Glassy)
Streak:
white
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