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| Formula | (Mn,Ca,Mg,Fe)SiO3 |
| | Optic class & sign | Biaxial positive |
| | Optical orientation | a near X, b near Y, c near Z |
| | Optical plane | Approx. orthogonal to (100) |
| | Relief | High |
| | Refractive indices | nx = 1.711 -1.738
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ny = 1.715 -1.741
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nz = 1.724 -1.751
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| n decreases with increasing Ca and Mg |
| | Birefringence (max.) | 0.011 - 0.014 |
| | | Δn decreases with increasing Ca and Mg |
| | Optic Angle
| 2Vx
|
| | 2Vz
= 58 - 87° |
| | Sign of elongation | Length-fast, l (-) in elongate cross-sections of tabular crystals |
| | Interference figure | Large-2V isogyres on a 1st order white background |
| | Colour / pleochroism | Colourless to pale pink; if coloured, weakly pleochroic |
| | Zoning | |
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| Form | Habit | Tabular ∥ {001}, granular |
| | | Surface | Anhedral to euhedral |
| | Cleavage | {110} and {110} perfect, {001} good |
| | Twinning | Not common |
| | Extinction | Inclined |
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| Reaction textures | |
| | Alteration / decomposition | Rhodochrosite, Mn oxides and hydroxides |
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| Occurence | Ign | Rarely in pegmatite |
| | | Met | Skarns |
| | | Sed | |
| | | Hyd | Hydrothermal ore deposits |
| | | Other | |
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| Distinctive properties | Low Δn, low crystal symmetry, pink colour in hand specimen, mineral association |
| | Additional comments | Exsolution lamellae of diopside may be present on {001}. Limited solid solution between rhodonite and wollastonite |
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