The Wolframite Group

PropertyFerberiteWolframiteHuebnerite
FormulaFeWO4(Fe, Mn)WO4MnWO4
WO3 Content (%)76.376.576.6
Mn Content (%)0 – 3.63.6 – 14.514.5 – 18.1
Fe Content (%)18.4 – 14.714.7 – 3.73.7 – 0
Specific Gravity7.5gr/cc7.1 – 7.5 gr/cc7.2 – 7.3 gr/cc
Formwell defined crystalsirregular groups of radiating crystalsradiating thin crystals
Colorblackdark grey to blackred-brown to black
Lustersubmetallic to metallicsubmetallic to metallicsubmetallic to adamantine
Diaphaneityopaque to translucentopaqueopaque to translucent
Streakdark browndark brownred-brown to green-yellow
Crystal Structuremonoclinicmonoclinicmonoclinic
Cleavage1 direction, perfect1 direction, perfect1 direction, perfect
Fractureunevenunevenuneven
Hardness5 Mohs5 -5.5 Mohs5 Mohs
Magnetismfeebleslightnone