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| Formula | CaMn(CO3)2 |
| | Optic class & sign | Uniaxial negative |
| | Relief | Moderate to high |
| | Refractive indices | no = 1.710 -1.727
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ne = 1.519 -1.535
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| n decreases with increasing Mg |
| | Birefringence (max.) | 0.191 - 0.192 |
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| | Sign of elongation | Hardly applicable due to very high Δn |
| | Interference figure | Well-defined isogyre cross, isochromes over multiple colour orders |
| | Colour / pleochroism | Colourless |
| | Zoning | |
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| Form | Habit | Granular aggregates |
| | | Surface | |
| | Cleavage | 3 sets, rhombohedral {1011}, perfect |
| | Twinning | |
| | Extinction | Symmetrical to cleavage traces in sections subparallel to c. Mottled extinction due to abundant miniscule breakouts at cleavage intersections. |
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| Reaction textures | |
| | Alteration / decomposition | |
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| Occurence | Ign | |
| | | Met | |
| | | Sed | Associated with sedimentary Mn deposits |
| | | Hyd | Hydrothermal deposits |
| | | Other | |
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| Distinctive properties | High-order white interference colours, rhombohedral cleavage, and relief change between nO and nE (as for all other rhombohedral carbonates). Mineral association. |
| | Additional comments | n-Δn chart: Cal - calcite, Dol - dolomite, Kut - kutnahorite, Mgs - magnesite, Rds - rhodochrosite, Sid - siderite, Smt - smithsonite |
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