Conchoidal - Fractures developed in brittle materials characterized by smoothly curving surfaces, (e.g. quartz).
Habit:
Irregular Grains - Occurs as splotchy, anhedral crystals forming inclusions in other minerals or rocks.
Habit:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Hardness:
5.5-6.5 - Knife Blade-Pyrite
Luster:
Vitreous - Metallic
Streak:
reddish brown
Optical Properties of Fergusonite-(Ce)
Gladstone-Dale:
CI meas= -0.114 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= 0.123 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1796,KPDmeas= 0.2281,KC= 0.2047 Ncalc = 2.12 - 2.42
Optical Data:
Uniaxial (-), e=2.2, w=2.3, bire=0.1000.
Calculated Properties of Fergusonite-(Ce)
Electron Density:
Bulk Density (Electron Density)=4.86 gm/cc note: Specific Gravity of Fergusonite-(Ce) =5.48 gm/cc.
Fermion Index:
Fermion Index = 0.0002378191 Boson Index = 0.9997621809
Photoelectric:
PEFergusonite-(Ce) = 268.98 barns/electron U=PEFergusonite-(Ce) x relectron=1,308.53 barns/cc.
Radioactivity:
GRapi = 40,097.09 (Gamma Ray American Petroleum Institute Units)
Concentration of Fergusonite-(Ce) per GRapi unit = 24.94 (PPM)
Fergusonite-(Ce) 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)
758.58 ±189.64 grams of pure Fergusonite-(Ce) .
Estimated Radioactivity from Fergusonite-(Ce) - weak
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 / 7.04 cm
948,539
2.56E-05
40,097.09
13.18
100 gm / 3.27 cm
94,854
2.56E-06
4,009.71
1.32
10 gm / 1.52 cm
9,485
2.56E-07
400.97
0.13
1 gm / 7.04 mm
949
2.56E-08
40.10
0.01
0.1 gm / 3.27 mm
95
2.56E-09
4.01
0.00
0.01 gm / 1.52 mm
9
2.56E-10
0.40
0.00
0.001 gm / 0.70 mm
1
2.56E-11
0.04
0.00
Weight of pure Fergusonite-(Ce) in grams (gm) and Calculated Diameter of a Sphere with a Density of 5.48 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 ( 2.12 % Th) From Sum REE Elements (42.35 % REE)
Fergusonite-(Ce) Classification
Dana Class:
08.01.01.03(08)Multiple Oxides with Nb, Ta, and Ti