Oligoclase
Chemical Formula	(Ca,Na)(Al,Si)4O8, where Ca/(Ca + Na) (% anorthite) is between 10%–30%
Species	Silicates
Mohs Scale	6
Specific Gravity	2.64-2.66
Color	usually white, with shades of grey, green, or red.
Streak	White
Luster	Vitreous
Refractive Index	nα=1.533–1.543; nβ=1.537–1.548; nγ=1.542–1.552
Diaphaneity	Translucent
Cleavage	Perfect
Fracture	Step-Like