2" Golden Rutile Crystals on Hematite - Brazil

Rutile is an oxide mineral composed primarily of TiO2, though iron is a typical chemical variation. It comes in a wide variety of crystal forms, from lustrous metallic-looking crystals and thin straw-like crystals to even deep red crystals with slight translucence. Rutile also forms needle-like inclusion with other minerals, most commonly with quartz. Rarer polymorphs of rutile (TiO2) include anatase and brookite, both of which have unique crystal structures.

Hematite is a fairly common mineral, typically responsible for the red-brown colorations found in other minerals and rocks. Its chemical composition is Fe2O3, occasionally containing small amounts of titanium (variable formula (Fe,Ti)2O3). Much of the time, non-crystalline hematite specimens are the result of a transformation from limonite following loss of water.