Asselbornite

Formula:  (Pb, Ba)(UO₂)₆(BiO)₄(AsO₄)₂(OH)₁₂^.3H₂O

Origin of name:  For Eric Asselborn (1954- ), French mineral collector and surgeon, Dijon, France, in whose collection the mineral was first found

Crystal system:  Cubic

Crystal class:  4/m -3 2/m, 432, 2/m -3 or 23

Twinning:

Unit cell: a = 15.66 Å

Colour:  Brown to yellow

Diaphaneity: Translucent

Luster:  Greasy to adamantine

Habit:  Cubes modified by tetrahedra or pseudo-tetrahedra

Hardness: 3

Specific gravity:  5.6 (calculated)

Cleavage: None

Tenacity:

Streak: lemon yellow

Synonyms/varieties:

Comments: Radioactive.