Veatchite-A

Formula: Sr₂B₁₁O₁₆(OH)₅.H₂O

Origin of name: for John Veach, American

Crystal system: Triclinic

Crystal class: 1 or -1

Twinning: on {100} polysynthetic lamellae observed optically

Unit cell: a = 20.8, b = 11.72, c = 6.63, α = 90°, β = 90.8°, γ = 91.95°

Colour: Colourless, white

Diaphaneity: Transparent

Luster: Pearly on cleavages

Habit: crystals platy, elongated or slender prismatic to fibrous, cross-fiber veins and divergent groups

Hardness: n.d.

Specific gravity: 2.77

Cleavage: 2; {100} perfect, {011}and {01-1} good

Tenacity: 

Streak: 

Synonyms/varieties:

Comments: trimorphous species with the names veatchite, p-veatchite and veatchite-A, all have similar properties but different crystal symmetry, crystal class is given for veatchite