Ulrichite

Formula: CaCu(UO₂)(PO₄)₂.4H₂O

Origin of name: for George F. Ulrich, German-Australian mineralogist

Crystal system: Monoclinic

Crystal class: 2/m

Twinning: on {100}

Unit cell: a = 12.79 Å, b = 6.85 Å, c = 13.02 Å, b = 91.0°

Colour: Pale apple green, lime green

Diaphaneity: Transparent to translucent

Luster: Vitreous

Habit: Crystals acicular to 0.05 by 1 mm in radiating sprays, as flat prisms

Hardness: 3.5

Specific gravity: 

Cleavage: None

Tenacity: 

Streak: White

Synonyms/varieties:

Comments: soluble in dilute HCl and HNO₃, radioactive