Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Hardness:
6 - Orthoclase
Luminescence:
Radioactive and Non-Fluorescent.
Luster:
Vitreous (Glassy)
Streak:
grayish brown
Optical Properties of Allanite-(La)
Gladstone-Dale:
CI meas= 0.034 (Excellent) - where the CI = (1-KPDmeas/KC) CI calc= 0.039 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1924,KPDmeas= 0.1934,KC= 0.2002 Ncalc = 1.79
Bulk Density (Electron Density)=3.77 gm/cc note: Specific Gravity of Allanite-(La) =3.93 gm/cc.
Fermion Index:
Fermion Index = 0.01 Boson Index = 0.99
Photoelectric:
PEAllanite-(La) = 98.10 barns/electron U=PEAllanite-(La) x relectron= 369.64 barns/cc.
Radioactivity:
GRapi = 5,105.45 (Gamma Ray American Petroleum Institute Units)
Concentration of Allanite-(La) per GRapi unit = 195.87 (PPM)
Allanite-(La) is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.
Estimated Radioactivity from Allanite-(La) - 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 / 7.86 cm
111,830
3.02E-06
5,105.45
1.68
100 gm / 3.65 cm
11,183
3.02E-07
510.54
0.17
10 gm / 1.69 cm
1,118
3.02E-08
51.05
0.02
1 gm / 7.86 mm
112
3.02E-09
5.11
0.00
0.1 gm / 3.65 mm
11
3.02E-10
0.51
0.00
0.01 gm / 1.69 mm
1
3.02E-11
0.05
0.00
0.001 gm / 0.79 mm
0
3.02E-12
0.01
0.00
Weight of pure Allanite-(La) in grams (gm) and Calculated Diameter of a Sphere with a Density of 3.93 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
Allanite-(La) Classification
Dana Class:
58.02.01c.02(58)Sorosilicate Insular, Mixed, Single, and Larger Tetrahedral Groups
(58.02)with cations in [6] and higher coordination; single and double groups (n=1,2)
Chemical Formula: 
Small.jpg)
- mild