Earthy - Dull, clay-like fractures with no visible crystalline affinities, (e.g. howlite).
Habit:
Earthy - Dull, clay-like texture with no visible crystalline affinities, (e.g. howlite).
Hardness:
1.5-2 - Talc-Gypsum
Luminescence:
Non-fluorescent.
Luster:
Earthy (Dull)
Streak:
white
Optical Properties of Nontronite
Gladstone-Dale:
CI meas= 0.051 (Good) - where the CI = (1-KPDmeas/KC) CI calc= 0.043 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2523,KPDmeas= 0.2501,KC= 0.2636 Ncalc = 1.6 - 1.61
Optical Data:
Biaxial (-), a=1.53-1.58, b=1.555-1.612, g=1.56-1.615, bire=0.0300-0.0350, 2V(Calc)=32-46, 2V(Meas)=5-66. Dispersion r > v strong.
Pleochroism (x):
yellowish green or yellowish green.
Pleochroism (y):
olive green or brownish green.
Pleochroism (z):
olive green or brownish green.
Calculated Properties of Nontronite
Electron Density:
Bulk Density (Electron Density)=2.28 gm/cc note: Specific Gravity of Nontronite =2.28 gm/cc.
Fermion Index:
Fermion Index = 0.01 Boson Index = 0.99
Photoelectric:
PENontronite = 7.45 barns/electron U=PENontronite x rElectron Density= 17.00 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Nontronite is Not Radioactive
Nontronite Classification
Dana Class:
71.03.01a.03(71)Phyllosilicate Sheets of Six-Membered Rings