Hübnerite

Hubnerite named after German mineralologist, Adolf Huebner. Hubnerite chemical formula: MnWO4. Has a molecular weight of 302.79 gm. manganese makes up 18.14% of chemical composition, tungsten: 60.72%, Oxygen: 21.14%. cleavage:[010] Perfect. color: Brown, reddish brown, brownish black. density: 7.15. fracture: brittle. hardness: 4.5-between flourite and apatite. luster: submetallic. streak: red-brown. diaphaniety:Transparent to translucent. crystalline structure: monoclinic-prismatic. For more info, go to http://webmineral.com