tetragonal Tungstates
Scheelite
Formula CaWO4
Crystal Structure
#! Species: Scheelite
#! System: Tetragonal (4/m)
#! Habit: Dipyramidal with strong fluorescence
tetragonal[4/m]:{112}@1.0 + {011}@0.7 + {001}@0.4
tetragonal
4/m
{112} {011} {001}
Quick Facts
Hardness
4.5
Specific Gravity
5.9
Refractive Index
1.918
Optical Character
Uniaxial +
Physical Properties
- Crystal System
- tetragonal
- Hardness (Mohs)
- 4.5
- Specific Gravity
- 5.9
- Cleavage
- Distinct {101}, poor {112}
- Fracture
- Subconchoidal to uneven
- Lustre
- Vitreous to adamantine
Optical Properties
- Refractive Index
- 1.918
- Birefringence
- 0.016-0.017
- Optical Character
- Uniaxial +
- Dispersion
- 0.026
- Pleochroism
- None
- Fluorescence
- Strong blue-white (SWUV) - diagnostic
Characteristics
Colours
ColorlessWhiteYellowOrangeBrownPale green
Localities
ChinaBrazilCalifornia (USA - Pine Creek)AustriaKoreaBolivia
Crystal Forms
dipyramidpinacoidpseudo-octahedral
Notes
Trace molybdenum shifts fluorescence to yellowish-green; important tungsten ore
Related Minerals
Other minerals in the tetragonal system
