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Uralborite

A valid IMA mineral species
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About UralboriteHide

Formula:
Ca2[B3O3(OH)5 · OB(OH)3]
Colour:
Colourless
Lustre:
Vitreous
Hardness:
4 - 4½
Specific Gravity:
2.58 - 2.60
Crystal System:
Monoclinic
Name:
The name reflects its discovery locality and composition: a borate.
This page provides mineralogical data about Uralborite.


Unique IdentifiersHide

Mindat ID:
4097
Long-form identifier:
mindat:1:1:4097:2

IMA Classification of UralboriteHide

Classification of UralboriteHide

6.DA.35

6 : BORATES
D : Tetraborates
A : Neso-tetraborates
25.3.4.1

25 : ANHYDROUS BORATES CONTAINING HYDROXYL OR HALOGEN
3 : Triborates
9.3.4

9 : Borates
3 : Borates of Ca and Sr

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

SymbolSourceReference for Standard
UboIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of UralboriteHide

Vitreous
Transparency:
Transparent
Colour:
Colourless
Hardness:
4 - 4½ on Mohs scale
Cleavage:
Distinct/Good
One, parallel to elongation, distinct.
Density:
2.58 - 2.60 g/cm3 (Measured)    2.58 g/cm3 (Calculated)

Optical Data of UralboriteHide

Type:
Biaxial (+)
RI values:
nα = 1.604 - 1.605 nβ = 1.609 - 1.611 nγ = 1.615 - 1.618
2V:
Measured: 85° , Calculated: 86°
Max. Birefringence:
δ = 0.011 - 0.013
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.

Surface Relief:
Moderate
Dispersion:
r > v
Comments:
anomalous dark blue and brown interference colors may be observed

Chemistry of UralboriteHide

Mindat Formula:
Ca2[B3O3(OH)5 · OB(OH)3]
Element Weights:
Element% weight
O59.357 %
Ca24.781 %
B13.369 %
H2.493 %

Calculated from ideal end-member formula.

Crystallography of UralboriteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Cell Parameters:
a = 6.925(2) Å, b = 12.328(3) Å, c = 9.833(3) Å
β = 97.50(40)°
Ratio:
a:b:c = 0.562 : 1 : 0.798
Unit Cell V:
832.28 ų (Calculated from Unit Cell)
Z:
4
Comment:
Space Group: P21/n.

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0012456UralboriteSimonov M A, Egorov-Tismenko Y K, Belov N V (1977) Accurate crystal structure of uralborite, Ca2[B4O4(OH)8] Doklady Akademii Nauk SSSR 234 822-82519770293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
7.61 Å(10)
2.13 Å(10)
2.97 Å(9)
1.407 Å(8)
6.18 Å(6)
3.42 Å(6)
4.81 Å(5)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Near-surface Processes
23 : Subaerial aqueous alteration by non-redox-sensitive fluids (see also #47)

Type Occurrence of UralboriteHide

Place of Conservation of Type Material:
Vernadsky Geological Museum, Moscow, 48613; A.E. Fersman Mineralogical Museum, Academy of Sciences, Moscow, Russia, 64944, vis3597.
Associated Minerals at Type Locality:

Other Language Names for UralboriteHide

Related Minerals - Strunz-mindat GroupingHide

6.DA.10BoraxNa2(B4O5)(OH)4 · 8H2OMon. 2/m : B2/b
6.DA.15TincalconiteNa2(B4O7) · 5H2OTrig. 32 : R32
6.DA.20HungchaoiteMg(B4O7) · 9H2OTric. 1 : P1
6.DA.25RoweiteCa2Mn2+2B4O7(OH)6Orth. mmm(2/m2/m2/m) : Pbam
6.DA.25FedorovskiteCa2Mg2B4O7(OH)6Orth. mmm(2/m2/m2/m) : Pbam
6.DA.30HydrochlorboriteCa4B8O15Cl2 · 21H2OMon. 2/m
6.DA.40NumanoiteCa4Cu(B4O6(OH)6)(CO3)2Mon. 2/m : B2/m
6.DA.40BorcariteCa4Mg(B4O6(OH)6)(CO3)2Mon. 2/m : B2/m
6.DA.60Fontarnauite(Na,K)2(Sr,Ca)(SO4)[B5O8(OH)] · 2H2OMon. 2/m : P21/b

Fluorescence of UralboriteHide

Fluoresces violet under LW UV.

Other InformationHide

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 UralboriteHide

References for UralboriteHide

Localities for UralboriteHide

Showing 2 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
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Locality ListHide

- 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). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.
Japan
 
  • Okayama Prefecture
    • Takahashi City
      • Bitchū
        • Fuka
Kusachi et al. (2000) +2 other references
Russia (TL)
 
  • Sverdlovsk Oblast
    • Serovsky District
      • Turya river
        • Tur'insk
[AmMin 85:1322] +1 other reference
 
and/or  
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