In silicate and carbonate cavities and in pegmatites in nepheline syenite. The Mn-dominant analogue of caresite and quintinite.
IMA Status:
Approved IMA 1995
Locality:
Mt. St.-Hilaire, QUE, Canada. Link to MinDat.org Location Data.
Name Origin:
Named for Charles (1917-) and Marcelle (1918-) Weber, amateur mineralogist of Guilford, CT, who contributed extensively to the knowledge of Mt. St.-Hilaire and also found the minera l.
Synonym:
IMA1992-027
Charmarite-3T Crystallography
Axial Ratios:
a:c = 1:2.05942
Cell Dimensions:
a = 10.9885, c = 22.63, Z = 6; V = 2,366.42 Den(Calc)= 2.49
Tabular - Form dimensions are thin in one direction.
Hardness:
2 - Gypsum
Luster:
Vitreous (Glassy)
Optical Properties of Charmarite-3T
Gladstone-Dale:
CI meas= 0.051 (Good) - where the CI = (1-KPDmeas/KC) CI calc= 0.047 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2277,KPDmeas= 0.2268,KC= 0.2389 Ncalc = 1.59 - 1.6
Optical Data:
Uniaxial (-), e=1.547, w=1.587, bire=0.0400.
Calculated Properties of Charmarite-3T
Electron Density:
Bulk Density (Electron Density)=2.47 gm/cc note: Specific Gravity of Charmarite-3T =2.49 gm/cc.
Fermion Index:
Fermion Index = 0.0004613895 Boson Index = 0.9995386105
Photoelectric:
PECharmarite-3T = 9.61 barns/electron U=PECharmarite-3T x rElectron Density= 23.78 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Charmarite-3T is Not Radioactive