Teruggite

Formula: Ca₄MgAs₂B₁₂O₂₂(OH)₁₂.12H₂O

Origin of name: for Mario E. Teruggi, professor of geology, universidad nacional La Plata (Argentina).

Crystal system: Monoclinic

Crystal class: 2/m

Twinning:

Unit cell: a = 15.68, b = 19.9, c = 6.25, β = 100.083°

Colour: Colourless to white

Diaphaneity: Transparent

Luster: Vitreous

Habit: crystals acicular, elongated along c-axis, rhombic cross section, 30 to 110 micron, aggregated into cauliflower-shaped nodules

Hardness: 2.5

Specific gravity: 2.15

Cleavage: 2; {001} good, {110} fair

Tenacity: Brittle

Streak: White

Synonyms/varieties:

Comments: