Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
orthorhombicuncommonOxides
Brookite
TiO₂
This specimen features dark, tabular, often striated brookite crystals, appearing almost black, growing on or within clear to milky quartz crystals.
Brookite Physical Properties
Mohs Hardness
5.5Crystal System
orthorhombicLuster
vitreousStreak Color
yellowish-brown to whiteCleavage
poor on {120}Fracture
subconchoidal to unevenSpecific Gravity
3.87Colors
brown, black, reddish-brown, yellowish-brownTransparency
opaque to translucentType Locality
Gouveia, Minas Gerais, Southeast Region, BrazilMineral Group
OxidesUses
collector, minor ore of titaniumAssociated Minerals
quartzRarity
uncommonGeological Context
Brookite is a polymorph of titanium dioxide, typically forming under specific conditions of temperature and pressure in alpine veins, contact metamorphic rocks, and igneous rocks.
