General Information:
Chemical Formula:
(K,Na)(Si,Al)4O8
Environment:
Acid volcanic rocks.
Locality:
Common world wide occurrences.
Name Origin:
From the Greek sanis - "little plate" and idos - "to see."
Physical Properties:
Cleavage:
[001] Perfect, [010] Good
Color:
colorless, white, gray, yellowish white, or reddish white.
Density:
2.52
Diaphaniety:
Transparent to translucent
Habits:
Blocky - Crystal shape tends to be equant (e.g. feldspars)., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Massive - Granular - Common texture observed in granit e and other igneous rock.
Hardness:
6 - Orthoclase
Luminescence:
Non-fluorescent.
Luster:
Vitreous - Pearly
Streak:
white
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