Granitic pegmatite hosted by biotite and hornblende gneiss.
IMA Status:
Approved IMA 1998 (Dana # Added)
Locality:
Found in the Hradisko quarry, in the Rozn� lepidolite subtype of granitic pegmatite, northeastern part of the Str�zek Moldanubicum, Czech Republic. Link to MinDat.org Location Data.
Name Origin:
Named after George R. Rossman (1945-), California Institute of Technology, Pasadena, CA, USA, in recognition for his work on the spectroscopy of the tourmaline minerals.
Brittle - Generally displayed by glasses and most non-metallic minerals.
Habit:
Columnar - Forms columns
Habit:
Crystalline - Coarse - Occurs as well-formed coarse sized crystals.
Habit:
Striated - Parallel lines on crystal surface or cleavage face.
Hardness:
7 - Quartz
Luster:
Vitreous (Glassy)
Streak:
white
Optical Properties of Rossmanite
Gladstone-Dale:
CI meas= 0.017 (Superior) - where the CI = (1-KPDmeas/KC) CI calc= 0.023 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2101,KPDmeas= 0.2115,KC= 0.2151 Ncalc = 1.65
Optical Data:
Uniaxial (-), e=1.624, w=1.645, bire=0.0210.
Calculated Properties of Rossmanite
Electron Density:
Bulk Density (Electron Density)=2.97 gm/cc note: Specific Gravity of Rossmanite =3.00 gm/cc.
Fermion Index:
Fermion Index = 0.01 Boson Index = 0.99
Photoelectric:
PERossmanite = 1.44 barns/electron U=PERossmanite x rElectron Density= 4.28 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Rossmanite is Not Radioactive
Chemical Formula: 
