Variscite

Formula: AlPO₄.2H₂O

Origin of name: from Latin Variscia, old name of locality in Vogtland, Germany

Crystal system: Orthorhombic

Crystal class: 2/m 2/m 2/m

Twinning: uncommon on {201}

Unit cell: a = 9.90 Å, b = 9.66 Å,  c = 17.18 Å

Colour: Pale green to emerald-green, bluish green to colourless, may be pale shades of brown or yellow, rarely red

Diaphaneity: Transparent to translucent

Luster: Vitreous, massive material waxy to earthy

Habit: Crystals octahedral, rare, massive, crusts, veinlets and nodules, reniform

Hardness: 4.5

Specific gravity: 2.59

Cleavage: 2; {010} perfect, {001} poor

Tenacity: Uneven to splintery, conchoidal fracture when glassy

Streak: White

Synonyms/varieties: phosphochromite (Fe-rich variety), redondite (Fe-rich variety), barrandite (intermediate between variscite and strengite), bolivarite, lucinite, utahlite

Comments: dimorphous with metavariscite, series with strengite