Found in a peralkaline pegmatite. (lamprophyllite group; structure).
IMA Status:
Approved IMA 2004 (Dana # Added)
Locality:
Inagli alkaline-ultrabasic massif, Yakutia, Russia. Also in the Kovdor alkaline-ultrabasic massif, Kola Peninsula, Russia. Link to MinDat.org Location Data.
Name Origin:
Named as the Na & Ba dominant analogue of lamprophyllite.
Brittle - Uneven - Very brittle fracture producing uneven fragments.
Habit:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Hardness:
3 - Calcite
Luster:
Vitreous - Adamantine
Streak:
white
Optical Properties of Nabalamprophyllite
Gladstone-Dale:
CI meas= 0.102 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= 0.112 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2122,KPDmeas= 0.2145,KC= 0.239 Ncalc = 1.86 - 1.87
Optical Data:
Biaxial (+), a=1.75, b=1.755, g=1.799, bire=0.0490, 2V(Calc)=38, 2V(Meas)=40. Dispersion r > v strong.
Calculated Properties of Nabalamprophyllite
Electron Density:
Bulk Density (Electron Density)=3.37 gm/cc note: Specific Gravity of Nabalamprophyllite =3.58 gm/cc.
Fermion Index:
Fermion Index = 0.06 Boson Index = 0.94
Photoelectric:
PENabalamprophyllite = 97.75 barns/electron U=PENabalamprophyllite x relectron= 329.38 barns/cc.
Radioactivity:
GRapi = 10.49 (Gamma Ray American Petroleum Institute Units)
Concentration of Nabalamprophyllite per GRapi unit = 9.53 (%)
Estimated Radioactivity from Nabalamprophyllite - barely detectable
Nabalamprophyllite Classification
Dana Class:
56.02.06c.08(56)Sorosilicate Si2O7 Groups and O, OH, F. and H2O
(56.02)with cations in [4] and/or >[4] coordination
(56.02.06c)Seidozerite - Lamprophyllite group (Lamprophyllite subgroup)