Tellurite

Formula: TeO₂

Origin of name: from composition, containing tellurium

Crystal system: Orthorhombic

Crystal class: 2/m 2/m 2/m

Twinning:

Unit cell: a = 5.607, b = 12.034, c = 5.463

Colour: Straw-yellow to yellowish orange, white

Diaphaneity: Transparent

Luster: Adamantine to subadamantine

Habit: Crystals acicular, thin striated plates, pulverulent coatings, spherical radial masses

Hardness: 2

Specific gravity: 5.90

Cleavage: 1; {010} perfect

Tenacity: Flexible

Streak: White

Synonyms/varieties:

Comments: dimorphous with paratellurite, very slightly soluble in water