Brookite
Chemical Formula	TiO2
Species	Oxides & Hydroxides
Crystal System	Orthorhombic
Mohs Scale	5-6
Specific Gravity	4.08-4.18
Color	Brown, yellowish brown, or black
Streak	White, greyish or yellowish
Luster	Adamantine, Sub-Metallic
Refractive Index	n = 2.583 n = 2.584 n = 2.700
Diaphaneity	Translucent, Opaque
Cleavage	Poor/Indistincton , in traces on
Fracture	Irregular/Uneven, Sub-Conchoidal
Crystal Habit：Tabular and striated, pyramidal or pseudohexagonal
Geological Setting：An accessory mineral in alpine veins in gneiss and schist; in contact metamorphic zones and hydrothermal veinlets; a common detrital mineral.