Geminite

Formula:  Cu(AsO₃OH) ^. H₂O

Origin of name:  From Latin for twins

Crystal system:  Triclinic

Crystal class:  -1

Twinning:

Unit cell:

Colour:  Light green to sea green

Diaphaneity:  Transparent

Luster:  Vitreous

Habit:  Euhedral intergrown crystals to 0.06 x 0.3 mm

Hardness:  3 to 3.5

Specific gravity:  3.70

Cleavage:  1; {001} perfect

Tenacity:

Streak:  Pale green

Synonyms/varieties:

Comments: