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| Formula | (Ca,Mn)2NaH(SiO3)3 |
| | Optic class & sign | Biaxial positive |
| | Optical orientation | |
| | Optical plane | |
| | Relief | |
| | Refractive indices | nx = 1.592 -1.680
|
|
ny = 1.603 -1.682
|
|
nz = 1.630 -1.705
|
|
| |
| | Birefringence (max.) | 0.025 - 0.038 |
| | | |
| | Optic Angle
| 2Vx
|
| | 2Vz
= 33 - 63° |
| | Sign of elongation | |
| | Interference figure | |
| | Colour / pleochroism | |
| | Zoning | |
|
|
| Form | Habit | |
| | | Surface | |
| | Cleavage | |
| | Twinning | |
| | Extinction | |
|
|
| Reaction textures | |
| | Alteration / decomposition | |
|
|
| Occurence | Ign | |
| | | Met | |
| | | Sed | |
| | | Hyd | |
| | | Other | |
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|
| Distinctive properties | |
| | Additional comments | The relations as shown between crystal morphology and indicatrix are essentially those of pectolite as the indicatrix orientation in sérandite is not known in any detail. Pectolite has a higher 2V (45 - 63°) than sérandite (33 - 39°).
The name schizolite has been suggested for intermediate manganoan pectolite.
The data points plotted are from Schaller (1955), American Mineralogist 40, 1022-1031, and Deer et al. (1997).
The refractive indices and birefringence of the rare Li variety Tanohataite (Tnh), Mn2LiH(SiO3)3 have been added to the n-Δn chart. |
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