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| Formula | CaWO4 |
| | Optic class & sign | Uniaxial positive |
| | Relief | Very high |
| | Refractive indices | no = 1.918 -1.921
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ne = 1.935 -1.938
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| | Birefringence (max.) | 0.017 |
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| | Sign of elongation | Not sensibly applicable, unless crystal shape is known (elongate in c vs. tabular) |
| | Interference figure | Well-defined uniaxial cross, with first order interference colours |
| | Colour / pleochroism | Colourless to pale yellow, orange or red |
| | Zoning | May be colour-zoned |
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| Form | Habit | Dipyramidal crystals, tabular, granular |
| | | Surface | Euhedral to anhedral |
| | Cleavage | {101} |
| | Twinning | {110} contact or penetration twins, common |
| | Extinction | |
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| Reaction textures | |
| | Alteration / decomposition | |
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| Occurence | Ign | Granitic pegmatites, greisen |
| | | Met | Contact-metamorphic siliceous carbonate rocks |
| | | Sed | |
| | | Hyd | Medium- to high-temperature hydrothermal veins |
| | | Other | |
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| Distinctive properties | Very high relief, low Δn, uniaxial |
| | Additional comments | |
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