Brittle - Uneven - Very brittle fracture producing uneven fragments.
Habit:
Acicular - Occurs as needle-like crystals.
Habit:
Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).
Habit:
Divergent - Crystals radiate from a center without producing stellar forms.
Hardness:
4-5 - Fluorite-Apatite
Luster:
Vitreous - Greasy
Streak:
white
Optical Properties of Dachiardite-Na
Gladstone-Dale:
CI meas= 0.024 (Excellent) - where the CI = (1-KPDmeas/KC) CI calc= 0.041 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2173,KPDmeas= 0.2213,KC= 0.2266 Ncalc = 1.49 - 1.5
Optical Data:
Biaxial (-), a=1.471-1.48, b=1.475-1.481, g=1.476-1.485, bire=0.0050, 2V(Calc)=52-54, 2V(Meas)=52-92. Dispersion r < v moderate.
Calculated Properties of Dachiardite-Na
Electron Density:
Bulk Density (Electron Density)=2.18 gm/cc note: Specific Gravity of Dachiardite-Na =2.16 gm/cc.
Fermion Index:
Fermion Index = 0.01 Boson Index = 0.99
Photoelectric:
PEDachiardite-Na = 2.15 barns/electron U=PEDachiardite-Na x relectron= 4.70 barns/cc.
Radioactivity:
GRapi = 22.34 (Gamma Ray American Petroleum Institute Units)
Concentration of Dachiardite-Na per GRapi unit = 4.48 (%)
Estimated Radioactivity from Dachiardite-Na - barely detectable