Brookite In Quartz Classification
Brookite In Quartz
Colorless With Brown, Yellow Brown, Reddish Brown Inclusions
Refractive index, appearance, birefringence, optic character and optic figure. A bull's-eye optic figure is determinative for quartz; may also show Airy's spiral optic figure and Brazil-law twinning under crossed polarizing filters.
Brookite is a form of titanium dioxide.