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.

Thickness: 30 µm Order divisions

Rotation:

Surface Relief:

High (positive)
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.

Focus:

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.

Thickness: 30 µm

Stage rotation: 0°

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
O	59.357 %
Ca	24.781 %
B	13.369 %
H	2.493 %

Calculated from ideal end-member formula.

Elements listed:

B, Ca, H, O - search for minerals with similar chemistry

Crystallography of UralboriteHide

Crystal System:

Monoclinic

Class (H-M):

2/m - Prismatic

Space Group:

P2₁/c

Setting:

P2₁/n

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 Å³ (Calculated from Unit Cell)

Crystal StructureHide

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Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4

View
CIF File Best | x | y | z | a | b | c

Rotation
Stop | Start

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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)
0012456	Uralborite	Simonov M A, Egorov-Tismenko Y K, Belov N V (1977) Accurate crystal structure of uralborite, Ca2[B4O4(OH)8] Doklady Akademii Nauk SSSR 234 822-825		1977		0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Uralborite'
loop_
_publ_author_name
'Simonov M A'
'Egorov-Tismenko Y K'
'Belov N V'
_journal_name_full 'Doklady Akademii Nauk SSSR'
_journal_volume 234 
_journal_year 1977
_journal_page_first 822
_journal_page_last 825
_publ_section_title
;
 Accurate crystal structure of uralborite, Ca2[B4O4(OH)8]
;
_database_code_amcsd 0012456
_chemical_formula_sum 'Ca B2 O6 H4'
_cell_length_a 6.927
_cell_length_b 9.836
_cell_length_c 12.331
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 97.81
_cell_volume 832.367
_exptl_crystal_density_diffrn      2.581
_symmetry_space_group_name_H-M 'P 1 1 21/n'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2-z'
  '1/2-x,1/2-y,1/2+z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Ca1   0.30116   0.23861   0.74017   0.00823
Ca2   0.28021   0.86440   0.59960   0.00785
B1   0.25750   0.33610   0.99240   0.00861
B2   0.17570   0.52030   0.84750   0.00785
B3   0.31460   0.76570   0.83500   0.00849
B4   0.40080   0.59560   0.69530   0.00849
O1   0.13200   0.40770   0.92560   0.00963
O2   0.41240   0.27700   0.92970   0.00988
O3   0.24390   0.64930   0.90470   0.00785
O4   0.42610   0.87720   0.90040   0.01077
O5   0.09240   0.06490   0.84860   0.00963
O6   0.14750   0.82300   0.78060   0.00925
O7   0.31660   0.48610   0.76610   0.00798
O8   0.44450   0.72790   0.75100   0.00785
O9   0.48360   0.03690   0.70720   0.00849
O10   0.26860   0.61290   0.60110   0.01317
O11   0.15010   0.07450   0.58030   0.01102
O12   0.36190   0.28210   0.54600   0.01102
H1   0.13500   0.90500   0.81000   0.04813
H2   0.03000   0.08400   0.58200   0.05826
H3   0.05400   0.28800   0.47500   0.03926
H4   0.01800   0.50600   0.26800   0.06459
H5   0.15400   0.59000   0.44800   0.08232
H6   0.09500   0.08700   0.90600   0.07599
H7   0.02500   0.24100   0.05000   0.07219
H8   0.19100   0.54000   0.59400   0.10385
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Ca1 0.00785 0.00811 0.00874 0.00013 0.00000 -0.00013
Ca2 0.00785 0.00823 0.00760 0.00013 -0.00051 -0.00038
B1 0.00798 0.01001 0.00823 0.00177 0.00000 0.00051
B2 0.00811 0.00709 0.00861 0.00127 0.00177 0.00190
B3 0.00836 0.00937 0.00861 0.00101 0.00000 0.00051
B4 0.00836 0.00709 0.01038 0.00127 -0.00051 0.00101
O1 0.00709 0.01127 0.01102 -0.00076 -0.00139 0.00469
O2 0.00975 0.01153 0.00950 0.00190 0.00126 -0.00203
O3 0.00988 0.00684 0.00684 -0.00101 0.00076 0.00000
O4 0.01102 0.00950 0.01140 -0.00127 -0.00152 -0.00139
O5 0.00785 0.00912 0.01292 0.00190 -0.00342 0.00038
O6 0.00912 0.00937 0.00975 0.00215 -0.00063 0.00114
O7 0.00823 0.00646 0.00899 0.00000 0.00152 0.00089
O8 0.00798 0.00646 0.01038 -0.00025 0.00253 -0.00026
O9 0.00709 0.00849 0.01077 0.00089 0.00215 0.00000
O10 0.01418 0.01406 0.01140 0.00203 0.00367 0.00215
O11 0.00963 0.01279 0.01064 0.00165 0.00329 0.00494
O12 0.01266 0.00975 0.01038 -0.00241 -0.00076 -0.00456

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
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 Mode	Earliest Age (Ga)
Near-surface Processes
23 : Subaerial aqueous alteration by non-redox-sensitive fluids (see also #47)

Type Occurrence of UralboriteHide

Type Locality:

ⓘ Novofrolovskoye B-Cu deposit, Tur'insk, Turya river, Serovsky District, Sverdlovsk Oblast, Russia

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:

'Andradite-Grossular Series'

Frolovite

Magnetite

Szaibélyite

Reference:

Malinko, S.V. (1961) New boron minerals — uralborite and pentahydroborite. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva: 90(6): 673-681.

Other Language Names for UralboriteHide

Dutch:Uralboriet

German:Uralborit

Russian:Уралборит

Spanish:Uralborita

Related Minerals - Strunz-mindat Grouping Hide

6.DA.10	Borax	Na₂(B₄O₅)(OH)₄ · 8H₂O	Mon. 2/m : B2/b
6.DA.15	Tincalconite	Na₂(B₄O₇) · 5H₂O	Trig. 32 : R32
6.DA.20	Hungchaoite	Mg(B₄O₇) · 9H₂O	Tric. 1 : P1
6.DA.25	Roweite	Ca₂Mn²⁺₂B₄O₇(OH)₆	Orth. mmm(2/m2/m2/m) : Pbam
6.DA.25	Fedorovskite	Ca₂Mg₂B₄O₇(OH)₆	Orth. mmm(2/m2/m2/m) : Pbam
6.DA.30	Hydrochlorborite	Ca₄B₈O₁₅Cl₂ · 21H₂O	Mon. 2/m
6.DA.40	Numanoite	Ca₄Cu(B₄O₆(OH)₆)(CO₃)₂	Mon. 2/m : B2/m
6.DA.40	Borcarite	Ca₄Mg(B₄O₆(OH)₆)(CO₃)₂	Mon. 2/m : B2/m
6.DA.60	Fontarnauite	(Na,K)₂(Sr,Ca)(SO₄)[B₅O₈(OH)] · 2H₂O	Mon. 2/m : P2₁/c

Fluorescence of UralboriteHide

In UV light:

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

mindat.org URL:

https://www.mindat.org/min-4097.html
Please feel free to link to this page.

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Look for Uralborite in the Rock H. Currier Digital Library

External Links:

Look for Uralborite on Webmineral

Look for Uralborite on Wikipedia

Look for Uralborite on Mineralien Atlas

Raman and XRD data at RRUFF project

References and PDF downloads at RRUFF project

American Mineralogist Crystal Structure Database

Handbook of Mineralogy page PDF

Mineral Dealers:

Buy from D. Joyce minerals

References for UralboriteHide

Reference List:

Malinko, S.V. (1961) New boron minerals — uralborite and pentahydroborite. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva: 90(6): 673-681.

Fleischer, Michael; František, Čech (1962) New mineral names. American Mineralogist, 47 (11-12). 1482-1485

IMA (1967) International Mineralogical Association: Commission on New Minerals and Mineral Names. Mineralogical Magazine and Journal of the Mineralogical Society, 36 (277) 131-136 doi:10.1180/minmag.1967.036.277.20

Shashkin, D.N., Simonov, M.A., Belov, N.V. (1970) The crystal structure of uralborite Ca2[B4O4(OH)8]. Soviet Physics - Crystallography: 14: 1044-1046.

Simonov, M.A., Egorov-Tismenko, Y.K., Belov, N.V. (1977) Accurate crystal structure of uralborite, Ca2[B4O4(OH)8]. Doklady Akademii Nauk SSSR: 234: 822-825.

Simonov, M.A., Egorov-Tismenko, Y.K., Belov, N.V. (1977) Accurate crystal structure of uralborite, Ca2[B4O4(OH)8]. Soviet Physics - Doklady: 22: 277-279.

Grew, Edward S.; Anovitz, Lawrence M. - Eds. (1996) Boron - Mineralogy, Petrology and Geochemistry. Reviews in Mineralogy Vol. 33. Mineralogical Society of America p.862

European Journal of Mineralogy (1997): 9: 228.

Kusachi, Isao, Shiraga, Kanako, Kobayashi, Shoichi, Yamakawa, Junji, Takechi, Yasushi (2000) Uralborite from Fuka, Okayama Prefecture, Japan. Journal of Mineralogical and Petrological Sciences, 95 (4) 43-47 doi:10.2465/jmps.95.43

(2005) Uralborite. Handbook of Mineralogy. Mineralogical Society of America

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.

Hide all sections | Show all sections

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 ⓘ Fuka mine	Kusachi et al. (2000) +2 other references

Russia (TL)
Sverdlovsk Oblast Serovsky District Turya river Tur'insk ⓘ Novofrolovskoye B-Cu deposit (TL)	[AmMin 85:1322] +1 other reference

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Uralborite

About UralboriteHide

Unique IdentifiersHide

IMA Classification of UralboriteHide

Classification of UralboriteHide

Mineral SymbolsHide

Physical Properties of UralboriteHide

Optical Data of UralboriteHide