General Information:
Chemical Formula:
(Ca,Na)(Si,Al)4O8
Composition:
(Molecular Weight = 275.01 gm)
Sodium 1.67 % Na
Calcium 11.66 % Ca
Aluminum 17.66 % Al
Silicon 22.47 % Si
Oxygen 46.54 % O
Empirical Formula:
Na0.2Ca0.8Al1.8Si2.2O8
Environment:
Magmatic and metamorphic rocks.
IMA Status:
Not IMA Approved
Locality:
"Bytown," now Ottawa, Ontario, Canada.
Name Origin:
Named after its locality.
Physical Properties:
Cleavage:
[001] Perfect, [010] Good
Color:
colorless, gray, or white.
Density:
2.7 - 2.72, Average = 2.71
Diaphaniety:
Translucent to transparent
Habits:
Granular - Generally occurs as anhedral to subhedral crystals in matrix., Crystalline - Coarse - Occurs as well-formed coarse sized crystals., Striated - Parallel lines on crystal sur face or cleavage face.
Hardness:
7 - Quartz
Luminescence:
Non-fluorescent.
Luster:
Vitreous (Glassy)
Streak:
white
More details...