Found as sporadic, irregularly shaped grains up to 0.3-0.5 mm across in a peralkaline pegmatoid. Eudialyte group.
IMA Status:
Approved IMA 2005 (Dana # Added)
Locality:
Mt. Alluaiv, Lovozero alkaline massif, Kola Peninsula, Russia Link to MinDat.org Location Data.
Name Origin:
The name is derived from Latin dualis (dual) alluding to the dual taxonomic membership of this mineral, which is at the same time zirconosilicate and titanosilicate.
Synonym:
IMA2005-019
Dualite Crystallography
Axial Ratios:
a:c = 1:4.29025
Cell Dimensions:
a = 14.153, c = 60.72, Z = 3; V = 10,533.18 Den(Calc)= 2.82
Irregular Grains - Occurs as splotchy, anhedral crystals forming inclusions in other minerals or rocks.
Hardness:
5 - Apatite
Luster:
Vitreous (Glassy)
Streak:
white
Optical Properties of Dualite
Gladstone-Dale:
CI meas= -0.012 (Superior) - where the CI = (1-KPDmeas/KC) CI calc= -0.019 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2168,KPDmeas= 0.2153,KC= 0.2128 Ncalc = 1.6
Optical Data:
Uniaxial (+), w=1.61, e=1.613, bire=0.0030.
Calculated Properties of Dualite
Electron Density:
Bulk Density (Electron Density)=2.77 gm/cc note: Specific Gravity of Dualite =2.84 gm/cc.
Fermion Index:
Fermion Index = 0.02 Boson Index = 0.98
Photoelectric:
PEDualite = 30.33 barns/electron U=PEDualite x relectron= 84.17 barns/cc.
Radioactivity:
GRapi = 3,213.61 (Gamma Ray American Petroleum Institute Units)
Concentration of Dualite per GRapi unit = 311.18 (PPM)
Estimated Radioactivity from Dualite - mild
Specimen Size Weight/Volume (Sphere) *
Calculated Activity Bequerols (Bq)
Calculated Activity Curies (Ci)
Estimated Activity GR(api)
Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 8.76 cm
69,071
1.87E-06
3,213.61
1.06
100 gm / 4.07 cm
6,907
1.87E-07
321.36
0.11
10 gm / 1.89 cm
691
1.87E-08
32.14
0.01
1 gm / 8.76 mm
69
1.87E-09
3.21
0.00
0.1 gm / 4.07 mm
7
1.87E-10
0.32
0.00
0.01 gm / 1.89 mm
1
1.87E-11
0.03
0.00
0.001 gm / 0.88 mm
0
1.87E-12
0.00
0.00
Weight of pure Dualite in grams (gm) and Calculated Diameter of a Sphere with a Density of 2.84 gm/cc.*
Goverment Estimate of Average Annual Exposure (
360 mRem)
** Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem
Estimated Thorium Activity ( 0.15 % Th) From Sum REE Elements ( 3.07 % REE)
Chemical Formula: 
- mild