In a black crust in the lower portion of the oxidation zone.
IMA Status:
Approved IMA 1982
Locality:
Shinkolobwe, Shaba, Zaire. Link to MinDat.org Location Data.
Name Origin:
Named after Jacques Lepersonne (1909-), honorary head of the Department of Geology and Mineralogy, Musee Royale de l'Afrique Centrale, Brussels, Belgium.
Name Pronunciation:
Lepersonnite-(Gd) + Pronunciation
Lepersonnite-(Gd) Crystallography
Axial Ratios:
a:b:c =0.4189:1:0.3027
Cell Dimensions:
a = 16.23, b = 38.74, c = 11.73, Z = 2; V = 7,375.24 Den(Calc)= 4.01
Aggregates - Made of numerous individual crystals or clusters.
Habit:
Encrustations - Forms crust-like aggregates on matrix.
Habit:
Spherical - Spherical, rounded aggregates.
Luminescence:
Non-fluorescent and radioactive.
Luster:
Vitreous (Glassy)
Streak:
light yellow
Optical Properties of Lepersonnite-(Gd)
Gladstone-Dale:
CI meas= -0.098 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= -0.087 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1651,KPDmeas= 0.1668,KC= 0.1519 Ncalc = 1.6 - 1.61
Bulk Density (Electron Density)=3.46 gm/cc note: Specific Gravity of Lepersonnite-(Gd) =4.01 gm/cc.
Fermion Index:
Fermion Index = 0.02 Boson Index = 0.98
Photoelectric:
PELepersonnite-(Gd) =1,706.79 barns/electron U=PELepersonnite-(Gd) x relectron=5,901.57 barns/cc.
Radioactivity:
GRapi = 4,705,731.27 (Gamma Ray American Petroleum Institute Units)
Concentration of Lepersonnite-(Gd) per GRapi unit = 212.51 (PPB)
Lepersonnite-(Gd) is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.
Estimated Maximum U.S. Postal Shipping Size
(10 mRem/hr limit, Unshielded 10 cm box)
6.46 ± 1.62 grams of pure Lepersonnite-(Gd) .
Estimated Maximum U.S. Postal Shipping Size
(10 mRem/hr limit, Unshielded 100 cm box)
646.37 ±161.59 grams of pure Lepersonnite-(Gd) .
Estimated Radioactivity from Lepersonnite-(Gd) - very strong
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 / 7.81 cm
114,605,128
3.10E-03
4,705,731.27
1,547.09
100 gm / 3.62 cm
11,460,513
3.10E-04
470,573.13
154.71
10 gm / 1.68 cm
1,146,051
3.10E-05
47,057.31
15.47
1 gm / 7.81 mm
114,605
3.10E-06
4,705.73
1.55
0.1 gm / 3.62 mm
11,461
3.10E-07
470.57
0.15
0.01 gm / 1.68 mm
1,146
3.10E-08
47.06
0.02
0.001 gm / 0.78 mm
115
3.10E-09
4.71
0.00
Weight of pure Lepersonnite-(Gd) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.01 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 ( 0.14 % Th) From Sum REE Elements ( 2.89 % REE)