Boromuscovite
A valid IMA mineral species
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About Boromuscovite
Formula:
KAl2(BSi3O10)(OH)2
Colour:
White
Lustre:
Vitreous, Dull
Hardness:
2½ - 3
Specific Gravity:
2.81
Crystal System:
Monoclinic
Member of:
Name:
Named in allusion to its compostion, containing Boron, and its relationship to Muscovite.
Unique Identifiers
Mindat ID:
729
Long-form identifier:
mindat:1:1:729:4
Similar Names
| Bario-muscovite | A synonym of 'Barium-bearing Muscovite' |
IMA Classification of Boromuscovite
Approved
IMA Formula:
KAl2(Si3B)O10(OH)2
Approval year:
1989
First published:
1991
Type description reference:
Classification of Boromuscovite
9.EC.15
9 : SILICATES (Germanates)
E : Phyllosilicates
C : Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets
9 : SILICATES (Germanates)
E : Phyllosilicates
C : Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets
71.2.2a.9
71 : PHYLLOSILICATES Sheets of Six-Membered Rings
2 : Sheets of 6-membered rings with 2:1 layers
71 : PHYLLOSILICATES Sheets of Six-Membered Rings
2 : Sheets of 6-membered rings with 2:1 layers
17.5.7
17 : Silicates Containing other Anions
5 : Borosilicates
17 : Silicates Containing other Anions
5 : Borosilicates
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.
Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Bms | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
| Bms | Warr (2020) | Warr, L.N. (2020) Recommended abbreviations for the names of clay minerals and associated phases. Clay Minerals, 55, 261–264 doi:10.1180/clm.2020.30 |
Physical Properties of Boromuscovite
Vitreous, Dull
Transparency:
Opaque
Colour:
White
Streak:
White
Hardness:
2½ - 3 on Mohs scale
Cleavage:
Perfect
Perfect on {001}
Perfect on {001}
Parting:
Poor on {010}
Fracture:
Sub-Conchoidal
Density:
2.81 g/cm3 (Measured) 2.89 g/cm3 (Calculated)
Comment:
Calculated 2.89 (2M1) and 2.90 (1M)
Optical Data of Boromuscovite
Type:
Biaxial (-)
RI values:
nα = 1.557 nβ = 1.587 nγ = 1.593
2V:
Measured: 44° , Calculated: 46°
Max. Birefringence:
δ = 0.036
Based on recorded range of RI values above.
Based on recorded range of RI values above.
Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
Surface Relief:
Moderate (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).
Relative to Canada balsam mounting medium (n ≈ 1.537).
This shows the grain boundary and Becke line effect under plane-polarised
light, based on the contrast between this mineral's average refractive
index and the mounting medium. It does not take into account mineral
colouration.
In focus
Interference Figure:
This shows the idealized biaxial acute bisectrix (Bxa) interference figure
- the conoscopic view for a grain cut perpendicular to the acute bisectrix, using
this mineral's 2V. The two small white dots mark the melatopes - the points
where the two optic axes emerge - and are shown only when they fall within the
field of view. The coloured bands are isochromatics, and the dark bands are
isogyres.
Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Dispersion:
r > v strong
Chemistry of Boromuscovite
Mindat Formula:
KAl2(BSi3O10)(OH)2
Element Weights:
Common Impurities:
Ti,Fe,Mn,Mg,Ca,Li,Na,Cs,P
Crystallography of Boromuscovite
Polytype:
Formula:
Crystal System:
Class (H-M)
Space Group:
Space Group Setting:
Cell Parameters:
Ratio:
Unit Cell Volume (calc):
Z:
Comment:
| Boromuscovite-1M | Boromuscovite-2M1 |
|---|---|
| KAl2(BSi3O10)(OH)2 | KAl2(BSi3O10)(OH)2 |
| Monoclinic | Monoclinic |
| 2/m - Prismatic | 2/m - Prismatic |
| B2/b | B2/b |
| C2/c | C2/c |
| a = 5.077(1) Å, b = 8.775(3) Å, c = 10.061(2) Å β = 101.31(2)° | a = 5.075(1) Å, b = 8.794(4) Å, c = 19.815(25) Å β = 95.59(3)° |
| a:b:c = 0.579 : 1 : 1.147 | a:b:c = 0.577 : 1 : 2.253 |
| V 439.52 ų (Calculated from Unit Cell) | V 880.13 ų (Calculated from Unit Cell) |
| 4 | 2 |
| Space Group: [C2/c] (1M polytype by analogy to muscovite) | 2M1 polytype by analogy to muscovite |
Crystal Structure
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Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
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2x2x2 | 3x3x3 | 4x4x4
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Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure
| ID | Species | Reference | Link | Year | Locality | Pressure (GPa) | Temp (K) |
|---|---|---|---|---|---|---|---|
| 0005446 | Boromuscovite | Liang J, Hawthorne F C, Novak M, Cerny P (1995) Crystal-structure refinement of boromuscovite polytypes using a coupled Rietveld-static-structure energy-minimization method The Canadian Mineralogist 33 859-865 |  | 1995 | Recice, Czech Republic | 0 | 293 |
| 0005445 | Boromuscovite | Liang J, Hawthorne F C, Novak M, Cerny P (1995) Crystal-structure refinement of boromuscovite polytypes using a coupled Rietveld-static-structure energy-minimization method The Canadian Mineralogist 33 859-865 | | 1995 | Recice, Czech Republic | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 3.569 Å | (100) |
| 4.391 Å | (80) |
| 3.008 Å | (80) |
| 2.505 Å | (80) |
| 9.862 Å | (60) |
| 4.239 Å | (40) |
| 4.007 Å | (40) |
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Near-surface Processes | |
| 23 : Subaerial aqueous alteration by non-redox-sensitive fluids (see also #47) | |
| Stage 4b: Highly evolved igneous rocks | >3.0 |
| 34 : Complex granite pegmatites |
Type Occurrence of Boromuscovite
General Appearance of Type Material:
Pseudohexagonal crystals, to 4 μm
Place of Conservation of Type Material:
National Museum of Natural History, Washington, D.C., USA, 166821.
Geological Setting of Type Material:
Pegmatite
Associated Minerals at Type Locality:
Synonyms of Boromuscovite
Other Language Names for Boromuscovite
Relationship of Boromuscovite to other Species
Member of:
Other Members of Dioctahedral mica:
| Celadonite Subgroup | A subgroup of the dioctahedral mica group. | |
| Chromphyllite | KCr2(AlSi3O10)(OH)2 | Mon. 2/m : B2/b |
| 'Glauconite' | K0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2 | |
| Muscovite | KAl2(AlSi3O10)(OH)2 | Mon. 2/m : B2/b |
| Nanpingite | CsAl2(AlSi3O10)(OH,F)2 | Mon. 2/m : B2/b |
| 'Natro-glauconite' | (Na,K)(Fe3+,Al,Mg)2((Si,Al)4O10)(OH)2 | |
| Paragonite | NaAl2(AlSi3O10)(OH)2 | Mon. |
| Roscoelite | KV3+2(AlSi3O10)(OH)2 | Mon. 2/m : B2/b |
| Tobelite | (NH4)Al2(AlSi3O10)(OH)2 | Mon. 2/m : B2/m |
Common Associates
Associations Based on Photo Data:
| 15 photos of Boromuscovite associated with Lepidolite | |
| 10 photos of Boromuscovite associated with 'Smoky Quartz' | SiO2 |
| 8 photos of Boromuscovite associated with Elbaite | Na(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3(OH) |
| 8 photos of Boromuscovite associated with Quartz | SiO2 |
| 4 photos of Boromuscovite associated with Beryllonite | NaBePO4 |
| 1 photo of Boromuscovite associated with Orthoclase | K(AlSi3O8) |
| 1 photo of Boromuscovite associated with 'Cleavelandite' | Na(AlSi3O8) |
| 1 photo of Boromuscovite associated with Spessartine | Mn2+3Al2(SiO4)3 |
| 1 photo of Boromuscovite associated with Albite | Na(AlSi3O8) |
Related Minerals - Strunz-mindat Grouping
| 9.EC. | Meifuite | KFe6(Si7Al)O19(OH)4Cl2 |
| 9.EC. | Balestraite | KLi2V5+Si4O12 |
| 9.EC.05 | Talc | Mg3Si4O10(OH)2 |
| 9.EC.05 | Minnesotaite | Fe2+3Si4O10(OH)2 |
| 9.EC.05 | Willemseite | Ni3Si4O10(OH)2 |
| 9.EC.9.EC. | Voloshinite | Rb(LiAl1.5◻0.5)(Al0.5Si3.5)O10F2 |
| 9.EC.10 | Fluorluanshiweiite | KLiAl1.5(Si3.5Al0.5)O10F2 |
| 9.EC.10 | Garmite | CsLiMg2(Si4O10)F2 |
| 9.EC.10 | Gorbunovite | CsLi2(Ti,Fe)Si4O10(F,OH,O)2 |
| 9.EC.10 | Ferripyrophyllite | Fe3+Si2O5(OH) |
| 9.EC.10 | Manganiceladonite | K(MgMn3+◻)(Si4O10)(OH)2 |
| 9.EC.10 | Luanshiweiite | KLiAl1.5(Si3.5Al0.5)O10(OH)2 |
| 9.EC.10 | Pyrophyllite | Al2Si4O10(OH)2 |
| 9.EC.15 | Paragonite | NaAl2(AlSi3O10)(OH)2 |
| 9.EC.15 | Ferroaluminoceladonite | K(Fe2+Al◻)(Si4O10)(OH)2 |
| 9.EC.15 | Nanpingite | CsAl2(AlSi3O10)(OH,F)2 |
| 9.EC.15 | Ferroceladonite | K(Fe2+Fe3+◻)(Si4O10)(OH)2 |
| 9.EC.15 | Ganterite | Ba0.5(Na,K)0.5Al2(Si2.5Al1.5)O10(OH)2 |
| 9.EC.15 | Kreiterite | CsLi2Fe3+(Si4O10)F2 |
| 9.EC.15 | Roscoelite | KV3+2(AlSi3O10)(OH)2 |
| 9.EC.15 | Aluminoceladonite | K(MgAl◻)(Si4O10)(OH)2 |
| 9.EC.15 | Tobelite | (NH4)Al2(AlSi3O10)(OH)2 |
| 9.EC.15 | Tainiolite | KLiMg2(Si4O10)F2 |
| 9.EC.15 | Celadonite | K(MgFe3+◻)(Si4O10)(OH)2 |
| 9.EC.15 | Chromceladonite | K(MgCr◻)(Si4O10)(OH)2 |
| 9.EC.15 | Montdorite | KFe2+1.5Mn2+0.5Mg0.5Si4O10(F,OH)2 |
| 9.EC.15 | Chromphyllite | KCr2(AlSi3O10)(OH)2 |
| 9.EC.15 | 'UM1988-22-SiO:AlCaFFeHKLiMg' | KLiMgAl2Si3O10F2 |
| 9.EC.15 | Chernykhite | (Ba,Na)(V3+,Al,Mg)2((Si,Al)4O10)(OH)2 |
| 9.EC.15 | Muscovite | KAl2(AlSi3O10)(OH)2 |
| 9.EC.20 | Masutomilite | K(LiAlMn2+)[AlSi3O10]F2 |
| 9.EC.20 | Oxyphlogopite | K(Mg,Ti,Fe)3[(Si,Al)4O10](O,F)2 |
| 9.EC.20 | 'Chloroferrokinoshitalite' | (Ba,K)(Fe2+,Mg)3(Al2Si2O10)(Cl,OH,F)2 |
| 9.EC.20 | Siderophyllite | KFe2+2Al(Al2Si2O10)(OH)2 |
| 9.EC.20 | Sokolovaite | CsLi2Al(Si4O10)F2 |
| 9.EC.20 | Hendricksite | KZn3(Si3Al)O10(OH)2 |
| 9.EC.20 | Tetraferriphlogopite | KMg3(Si3Fe3+)O10(OH)2 |
| 9.EC.20 | Fluorannite | KFe2+3(Si3Al)O10F2 |
| 9.EC.20 | Aspidolite | NaMg3(AlSi3O10)(OH)2 |
| 9.EC.20 | Suhailite | (NH4)Fe2+3(AlSi3O10)(OH)2 |
| 9.EC.20 | Ephesite | NaLiAl2(Al2Si2O10)(OH)2 |
| 9.EC.20 | Norrishite | KLiMn3+2(Si4O10)O2 |
| 9.EC.20 | Phlogopite | KMg3(AlSi3O10)(OH)2 |
| 9.EC.20 | Yangzhumingite | KMg2.5(Si4O10)F2 |
| 9.EC.20 | Orlovite | KLi2Ti(Si4O10)OF |
| 9.EC.20 | Tetraferriannite | KFe2+3(Si3Fe3+)O10(OH)2 |
| 9.EC.20 | Shirokshinite | K(NaMg2)(Si4O10)F2 |
| 9.EC.20 | Trilithionite | K(Li1.5Al1.5)(AlSi3O10)(F,OH)2 |
| 9.EC.20 | Polylithionite | KLi2Al(Si4O10)(F,OH)2 |
| 9.EC.20 | Shirozulite | KMn2+3(Si3Al)O10(OH)2 |
| 9.EC.20 | Preiswerkite | NaMg2Al(Al2Si2O10)(OH)2 |
| 9.EC.20 | Fluorophlogopite | KMg3(Si3Al)O10F2 |
| 9.EC.20 | Wonesite | (Na,K,◻)(Mg,Fe,Al)6(Si,Al)8O20(OH,F)4 |
| 9.EC.20 | 'UM2004-49-SiO:AlCsFHKLi' | (Cs,K)(Al,Li)2.6((Si,Al)4O10)(F,OH)2 |
| 9.EC.20 | Fluorotetraferriphlogopite | KMg3(Fe3+Si3O10)F2 |
| 9.EC.20 | Annite | KFe2+3(AlSi3O10)(OH)2 |
| 9.EC.20 | Eastonite | KMg2Al(Al2Si2O10)(OH)2 |
| 9.EC.22 | 'Pimelite' | Ni3Si4O10(OH)2 · 4H2O |
| 9.EC.30 | Margarite | CaAl2(Al2Si2O10)(OH)2 |
| 9.EC.35 | Kinoshitalite | (Ba,K)(Mg,Mn2+,Al)3(Al2Si2O10)(OH)2 |
| 9.EC.35 | Ferrokinoshitalite | (Ba,K)(Fe2+,Mg)3(Al2Si2O10)(OH,F)2 |
| 9.EC.35 | Clintonite | CaAlMg2(SiAl3O10)(OH)2 |
| 9.EC.35 | Oxykinoshitalite | (Ba,K)(Mg,Ti,Fe3+,Fe2+)3((Si,Al)4O10)(O,OH,F)2 |
| 9.EC.35 | Fluorokinoshitalite | BaMg3(Al2Si2O10)F2 |
| 9.EC.35 | Bityite | CaLiAl2(AlBeSi2O10)(OH)2 |
| 9.EC.35 | Anandite | (Ba,K)(Fe2+,Mg)3((Si,Al,Fe)4O10)(S,OH)2 |
| 9.EC.40 | Montmorillonite | (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O |
| 9.EC.40 | Beidellite | (Na,Ca0.5)0.3Al2((Si,Al)4O10)(OH)2 · nH2O |
| 9.EC.40 | Volkonskoite | Ca0.3(Cr,Mg,Fe)2((Si,Al)4O10)(OH)2 · 4H2O |
| 9.EC.40 | Nontronite | Na0.3Fe2((Si,Al)4O10)(OH)2 · nH2O |
| 9.EC.40 | Kurumsakite | (Zn,Ni,Cu)8Al8V5+2Si5O35 · 27H2O (?) |
| 9.EC.40 | Yakhontovite | (Ca,Na)0.5(Cu,Fe,Mg)2(Si4O10)(OH)2 · 3H2O |
| 9.EC.45 | Swinefordite | Li(Al,Li,Mg)3((Si,Al)4O10)2(OH,F)4 · nH2O |
| 9.EC.45 | Hectorite | Na0.3(Mg,Li)3(Si4O10)(F,OH)2 |
| 9.EC.45 | Zincsilite | Zn3Si4O10(OH)2 · 4H2O (?) |
| 9.EC.45 | Hanjiangite | Ba2CaV3+Al(H2AlSi3O12)(CO3)2F |
| 9.EC.45 | Spadaite | MgSiO2(OH)2 · H2O (?) |
| 9.EC.45 | Ferrosaponite | Ca0.3(Fe2+,Mg,Fe3+)3((Si,Al)4O10)(OH)2 · 4H2O |
| 9.EC.45 | Stevensite | (Ca,Na)xMg3-x(Si4O10)(OH)2 |
| 9.EC.45 | Saponite | Ca0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O |
| 9.EC.45 | Sauconite | Na0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O |
| 9.EC.50 | Vermiculite | Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O |
| 9.EC.52 | 'Tarasovite' | near NaKAl11Si13O40(OH)9 · 3H2O |
| 9.EC.55 | Clinochlore | Mg5Al(AlSi3O10)(OH)8 |
| 9.EC.55 | Borocookeite | (LiAl4◻)[BSi3O10](OH)8 |
| 9.EC.55 | Franklinfurnaceite | Ca2Fe3+Mn2+3Mn3+(Zn2Si2O10)(OH)8 |
| 9.EC.55 | Pennantite | Mn2+5Al(AlSi3O10)(OH)8 |
| 9.EC.55 | Vakhrushevaite | Mg5Cr(AlSi3O10)(OH)8 |
| 9.EC.55 | Nimite | Ni5Al(AlSi3O10)(OH)8 |
| 9.EC.55 | Cookeite | (LiAl4◻)[AlSi3O10](OH)8 |
| 9.EC.55 | Gonyerite | Mn2+5Fe3+(Fe3+Si3O10)(OH)8 |
| 9.EC.55 | Chamosite | Fe2+5Al(AlSi3O10)(OH)8 |
| 9.EC.55 | 'Orthochamosite' | (Fe2+,Mg,Fe3+)5Al(AlSi3O10)(OH,O)8 |
| 9.EC.55 | Baileychlore | Zn5Al(AlSi3O10)(OH)8 |
| 9.EC.55 | Sudoite | Mg2Al3(AlSi3O10)(OH)8 |
| 9.EC.55 | Glagolevite | Na(Mg,Al)6(AlSi3O10)(OH,O)8 |
| 9.EC.55 | Donbassite | Al4.33(AlSi3O10)(OH)8 |
| 9.EC.60 | Dozyite | Mg7Al2(Al2Si4O15)(OH)12 |
| 9.EC.60 | Rectorite | (Na,Ca)Al4((Si,Al)8O20)(OH)4 · 2H2O |
| 9.EC.60 | Corrensite | (Mg,Fe)9((Si,Al)8O20)(OH)10 · nH2O |
| 9.EC.60 | Aliettite | Ca0.2Mg6((Si,Al)8O20)(OH)4 · 4H2O |
| 9.EC.60 | Karpinskite | (Ni,Mg)2Si2O5(OH)2 (?) |
| 9.EC.60 | Lunijianlaite | Li0.7Al6.2(AlSi7O20)(OH,O)10 |
| 9.EC.60 | Tosudite | Na0.5(Al,Mg)6((Si,Al)8O18)(OH)12 · 5H2O |
| 9.EC.60 | Hydrobiotite | K(Mg,Fe2+)6((Si,Al)8O20)(OH)4 · nH2O |
| 9.EC.60 | Saliotite | (Li,Na)Al3(AlSi3O10)(OH)5 |
| 9.EC.60 | Kulkeite | Mg8Al(AlSi7O20)(OH)10 |
| 9.EC.60 | Brinrobertsite | Na0.3Al4(Si4O10)2(OH)4 · 3.5 H2O |
| 9.EC.65 | Macaulayite | (Fe,Al)24Si4O43(OH)2 |
| 9.EC.70 | Burckhardtite | Pb2(Fe3+Te6+)[AlSi3O8]O6 |
| 9.EC.75 | Niksergievite | (Ba,Ca)2Al3(AlSi3O10)(CO3)(OH)6 · nH2O |
| 9.EC.75 | Ferrisurite | (Pb,Ca)2.4Fe3+2(Si4O10)(CO3)1.7(OH)3 · nH2O |
| 9.EC.75 | Surite | (Pb,Ca)3(Al,Fe2+,Mg)2((Si,Al)4O10)(CO3)2(OH)2 |
| 9.EC.80 | Kegelite | Pb8Al4(Si8O20)(SO4)2(CO3)4(OH)8 |
Radioactivity
Radioactivity:
| Element | % Content | Activity (Bq/kg) | Radiation Type |
|---|---|---|---|
| Uranium (U) | 0.0000% | 0 | α, β, γ |
| Thorium (Th) | 0.0000% | 0 | α, β, γ |
| Potassium (K) | 10.2315% | 3,172 | β, γ |
For comparison:
- Banana: ~15 Bq per fruit
- Granite: 1,000–3,000 Bq/kg
- EU exemption limit: 10,000 Bq/kg
Note: Risk is shown relative to daily recommended maximum exposure to non-background radiation of 1000 µSv/year. Note that natural background radiation averages around 2400 µSv/year so in reality these risks are probably extremely overstated! With infrequent handling and safe storage natural radioactive minerals do not usually pose much risk.
Interactive Simulator:
Note: The mass selector refers to the mass of radioactive mineral present, not the full specimen, also be aware that the matrix may also be radioactive, possibly more radioactive than this mineral!
Activity: –
| Distance | Dose rate | Risk |
|---|---|---|
| 1 cm | ||
| 10 cm | ||
| 1 m |
The external dose rate (D) from a radioactive mineral is estimated by summing the gamma radiation contributions from its Uranium, Thorium, and Potassium content, disregarding daughter-product which may have a significant effect in some cases (eg 'pitchblende'). This involves multiplying the activity (A, in Bq) of each element by its specific gamma ray constant (Γ), which accounts for its unique gamma emissions. The total unshielded dose at 1 cm is then scaled by the square of the distance (r, in cm) and multiplied by a shielding factor (μshield). This calculation provides a 'worst-case' or 'maximum risk' estimate because it assumes the sample is a point source and entirely neglects any self-shielding where radiation is absorbed within the mineral itself, meaning actual doses will typically be lower. The resulting dose rate (D) is expressed in microsieverts per hour (μSv/h).
D = ((AU × ΓU) + (ATh × ΓTh) + (AK × ΓK)) / r2 × μshield
Other Information
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Internet Links for Boromuscovite
mindat.org URL:
https://www.mindat.org/min-729.html
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References for Boromuscovite
Reference List:
Foord, Eugene E., Martin, Robert F., Fitzpatrick, Joan J., Taggart, Joseph E., Jr.,, Crock, James G. (1991) Boromuscovite, a new member of the mica group, from the Little Three mine pegmatite, Ramona district, San Diego County, California. American Mineralogist, 76 (11-12) 1998-2002
Localities for Boromuscovite
Showing 7 localities.
symbol to view information about a locality.
The Locality List
- This locality has map coordinates listed.
- This locality has estimated coordinates.
ⓘ - Click for references and further information on this occurrence.
? - Indicates mineral may be doubtful at this locality.
- Good crystals or important locality for species.
- World class for species or very significant.
(TL) - Type Locality for a valid mineral species.
(FRL) - First Recorded Locality for everything else (eg varieties).
All localities listed without proper references should be considered as questionable.
Canada | |
| Northern Mineral Showings Database |
Czech Republic | |
| Novák (1995) +1 other reference |
Pakistan | |
| Montgomery (n.d.) |
Russia | |
| Zagorsky et al. (2003) |
| Zagorsky et al. (2003) +2 other references | |
Tajikistan | |
| Chukanov (2014) |
USA (TL) | |
| Foord et al. (1989) +2 other references |
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Little Three Mine, Little Three Mine area, Ramona, Ramona Mining District, San Diego County, California, USA