Minor accessory mineral in a quartz vein cross-cutting deep purple, highly oxidized manganiferous Ordovician phyllites.
IMA Status:
Approved IMA 2004 (Dana # Added)
Locality:
Stavelot Massif at Le Coreux, 1 km north of Salmch�teau along the western flanks of the Salm river valley, Ardennes, Belgium. Link to MinDat.org Location Data.
Name Origin:
Named for the Stavelot Massif in the Belgian Ardennes Mountains, and Stavelot, which is a historical town in eastern Belgium.
Synonym:
IMA2004-014
Stavelotite-(La) Crystallography
Axial Ratios:
a:c = 1:2.89344
Cell Dimensions:
a = 11.525, c = 33.347, Z = 3; V = 3,835.92 Den(Calc)= 4.47
Unknown - Minerals too small to observe fractures.
Habit:
Aggregates - Made of numerous individual crystals or clusters.
Habit:
Anhedral Grains - Granular minerals without the expression of crystal shapes
Luster:
Metallic
Optical Properties of Stavelotite-(La)
Optical Data:
Uniaxial (?).
RL Anisotrophism:
Very weak.
RL Bireflectance:
Weak to very weak.
RL Color:
Gray.
RL Pleochroism:
Very weak with weak brown internal reflections in oil.
Reflectivity
Standardized Intensity (100%) Reflection Spectra of Stavelotite-(La) in Air
λ
R1
R2
∑ R1(λ)
∑ R2(λ)
470 nm
13.60
14.40
546 nm
13.20
13.90
589 nm
13.00
13.70
650 nm
12.80
13.40
Standardized Intensity (100%) Reflection Spectra of Stavelotite-(La) in Oil
λ
R1
R2
∑ R1(λ)
∑ R2(λ)
470 nm
3.00
3.70
546 nm
2.90
3.50
589 nm
2.80
3.40
650 nm
2.70
3.20
Calculated Relative Intensity Colors of Stavelotite-(La) in Air
Relative Intensity
0%
70%
100%
140%
210%
280%
350%
420%
490%
560%
630%
680%
R1
R2
Calculated Relative Intensity Colors of Stavelotite-(La) in Oil
Relative Intensity
0%
100%
200%
300%
400%
500%
600%
700%
800%
900%
1000%
R1
R2
Calculated Properties of Stavelotite-(La)
Electron Density:
Bulk Density (Electron Density)=4.22 gm/cc note: Specific Gravity of Stavelotite-(La) =4.47 gm/cc.
Fermion Index:
Fermion Index = 0.01 Boson Index = 0.99
Photoelectric:
PEStavelotite-(La) = 64.68 barns/electron U=PEStavelotite-(La) x relectron= 272.75 barns/cc.
Radioactivity:
GRapi = 10,839.46 (Gamma Ray American Petroleum Institute Units)
Concentration of Stavelotite-(La) per GRapi unit = 92.26 (PPM)
Stavelotite-(La) is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.
Estimated Radioactivity from Stavelotite-(La) - 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 / 7.53 cm
241,281
6.52E-06
10,839.46
3.56
100 gm / 3.50 cm
24,128
6.52E-07
1,083.95
0.36
10 gm / 1.62 cm
2,413
6.52E-08
108.39
0.04
1 gm / 7.53 mm
241
6.52E-09
10.84
0.00
0.1 gm / 3.50 mm
24
6.52E-10
1.08
0.00
0.01 gm / 1.62 mm
2
6.52E-11
0.11
0.00
0.001 gm / 0.75 mm
0
6.52E-12
0.01
0.00
Weight of pure Stavelotite-(La) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.47 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 ( 0.54 % Th) From Sum REE Elements (10.77 % REE)
Stavelotite-(La) Classification
Dana Class:
55.04.04.01(55)Sorosilicate Si2O7 Groups, Generally with No Additional Anions
Chemical Formula: 
- weak