Pale green, White, Gray white, Yellowish white, Brownish white.
Density:
2.7 - 2.8, Average = 2.75
Diaphaneity:
Translucent
Fracture:
Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.
Habit:
Foliated - Two dimensional platy forms.
Habit:
Massive - Uniformly indistinguishable crystals forming large masses.
Habit:
Scaly - Morphology like fish scales.
Hardness:
1 - Talc
Luminescence:
Fluorescent, Short UV=orange yellow, Long UV=yellow.
Luster:
Vitreous - Pearly
Streak:
white
Optical Properties of Talc
Gladstone-Dale:
CI meas= 0.018 (Superior) - where the CI = (1-KPDmeas/KC) CI calc= 0.042 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2028,KPDmeas= 0.208,KC= 0.2117 Ncalc = 1.57 - 1.6
Optical Data:
Biaxial (-), a=1.538-1.55, b=1.575-1.594, g=1.575-1.6, bire=0.0370-0.0500, 2V(Calc)=0-38, 2V(Meas)=0-30. Dispersion noticeable, r > v.
Pleochroism (x):
colorless.
Pleochroism (y):
pale green.
Calculated Properties of Talc
Electron Density:
Bulk Density (Electron Density)=2.76 gm/cc note: Specific Gravity of Talc =2.75 gm/cc.
Fermion Index:
Fermion Index = 0.03 Boson Index = 0.97
Photoelectric:
PETalc = 1.57 barns/electron U=PETalc x rElectron Density= 4.34 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Talc is Not Radioactive
Talc Classification
Dana Class:
71.02.01.03(71)Phyllosilicate Sheets of Six-Membered Rings
Chemical Formula: 
