Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).
Habit:
Crystalline - Fine - Occurs as well-formed fine sized crystals.
Habit:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Hardness:
3.5-4 - Copper Penny-Fluorite
Luminescence:
Fluorescent, Short UV=Weak white, Long UV=weak white.
Luster:
Vitreous (Glassy)
Streak:
white
Optical Properties of Laumontite
Gladstone-Dale:
CI meas= 0.017 (Superior) - where the CI = (1-KPDmeas/KC) CI calc= 0.004 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2274,KPDmeas= 0.2244,KC= 0.2282 Ncalc = 1.51 - 1.54
Optical Data:
Biaxial (-), a=1.502-1.519, b=1.512-1.525, g=1.513-1.526, bire=0.0070-0.0110, 2V(Calc)=34-44, 2V(Meas)=25-47. Dispersion marked to extreme, r < v.
Pleochroism (x):
colorless.
Pleochroism (y):
colorless.
Calculated Properties of Laumontite
Electron Density:
Bulk Density (Electron Density)=2.30 gm/cc note: Specific Gravity of Laumontite =2.27 gm/cc.
Fermion Index:
Fermion Index = 0.01 Boson Index = 0.99
Photoelectric:
PELaumontite = 2.32 barns/electron U=PELaumontite x rElectron Density= 5.33 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Laumontite is Not Radioactive
Chemical Formula: 
