Umohoite

Formula: (UO₂)MoO₄.4H₂O

Origin of name: combination of symbols for the elements present (U, Mo, H)

Crystal system: Triclinic

Crystal class: 1

Twinning:

Unit cell: a = 6.3748, b = 7.5287, c = 14.628, α = 82.64°, β = 85.95°, γ = 89.91

Colour: Dark blue, black to bluish black

Diaphaneity: Opaque to semitransparent

Luster: Submetallic to vitreous

Habit: crystals platy-like, tabular, fine-grained platy or foliated aggregates, rosettes, in thin veinlets, also massive and disseminated

Hardness: about 2

Specific gravity: 4.55 to 4.93

Cleavage: 1; {001} perfect

Tenacity: 

Streak: Blue gray

Synonyms/varieties:

Comments:  Radioactive