Hübnerite

Formula:  MnWO₄

Origin of name:  For A. Hübner, German metallurgist

Crystal system:  Monoclinic

Crystal class:  2/m

Twinning:  Common on {100}, contact, penetration, or rarely lamellar

Unit cell: a = 4.83 Ǻ, b = 5.76 Ǻ, c = 5.00 Ǻ, β = 91.2°

Colour:  Yellowish-brown to reddish-brown, brownish-black

Diaphaneity: 

Luster:  Submetallic to resinous

Habit:  Crystals short to long prismatic, flattened or tabular, striated parallel to elongation, in radial groups or subparallel groups

Hardness:  4 to 4.5

Specific gravity:  7.18

Cleavage:  1; {010} perfect

Tenacity:  Brittle

Streak:  Yellow to red-brown

Synonyms/varieties:

Comments:  Series with ferberite, used to be known as the wolframite series