Welshite

Formula: Ca₂SbMg₄FeSi₄Be₂O₂₀

Origin of name: for after Wilfred R. Welsh, science teacher, auxillary police officer, motorcycle enthusiast, and amateur mineralogist of upper Saddle River, New Jersey (USA). He was past President of the Franklin Mineral Museum and a significant benefactor to that institution, where his mineral and fossil collection now reside. This species was named in his honor by one of his former students: Dr. Paul Moore.

Crystal system: Triclinic

Crystal class: 1

Twinning: polysynthetic

Unit cell: a = 10.28, b = 10.69, c = 8.838, α = 106.1°, β = 96.3°, γ = 124°

Colour: Reddish brown to black, brown, orange brown, deep tan

Diaphaneity: Subtranslucent to opaque

Luster: Subadamantine

Habit: crystals thick prismatic, to 3 mm

Hardness: 6

Specific gravity: 3.77

Cleavage: None

Tenacity: Conchoidal fracture

Streak: Pale brown

Synonyms/varieties:

Comments: