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Hydrochlorborite

A valid IMA mineral species - grandfathered

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Hydrochlorborite

Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile

Hydrochlorborite

Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile

Hydrochlorborite

Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile

Hydrochlorborite

Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile

Hydrochlorborite

Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile

Hydrochlorborite

Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile

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About HydrochlorboriteHide

Formula:

Ca₄B₈O₁₅Cl₂ · 21H₂O

Lustre:

Vitreous, Dull

Hardness:

2½

Specific Gravity:

1.83 - 1.85

Crystal System:

Monoclinic

Co-Type Localities:

ⓘ Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile
ⓘ China

This page provides mineralogical data about Hydrochlorborite.

Unique IdentifiersHide

Mindat ID:

1970

Long-form identifier:

mindat:1:1:1970:1

IMA Classification of HydrochlorboriteHide

IMA status:

Approved, 'Grandfathered' (first described prior to 1959)

IMA Formula:

Ca₂B₄O₄Cl(OH)₇·7H₂O

Type description reference:

Qian Ziqiang, Chen Shuzhen, Ma Shinian, and Liu Xunjian (1965): Hydrochlorborite, a new hydrous chlor-borate mineral. Acta Geologica Sinica 45(2), 209-216 (in Chinese with English abstract).

Classification of HydrochlorboriteHide

Strunz-mindat (2026):

6.DA.30

6 : BORATES
D : Tetraborates
A : Neso-tetraborates

Dana 8th ed.:

26.3.4.1

26 : HYDRATED BORATES CONTAINING HYDROXYL OR HALOGEN
3 : Triborates

Hey's CIM Ref.:

10.1.12

10 : Borates with other anions
1 : Borates with halide

Mineral SymbolsHide

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

Symbol	Source	Reference for Standard
Hcb	IMA–CNMNC	Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of HydrochlorboriteHide

Lustre:

Vitreous, Dull

Transparency:

Transparent

Hardness:

2½ on Mohs scale

Tenacity:

Brittle

Cleavage:

Distinct/Good
{001}, good.

Fracture:

Conchoidal

Density:

1.83 - 1.85 g/cm³ (Measured) 1.841 g/cm³ (Calculated)

Optical Data of HydrochlorboriteHide

Type:

Biaxial (+)

RI values:

n_α = 1.499 - 1.501 n_β = 1.502 - 1.504 n_γ = 1.520 - 1.521

2V:

Measured: 45° to 46°, Calculated: 44°

Max. Birefringence:

δ = 0.020 - 0.021
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.

Thickness: 30 µm Order divisions

Rotation:

Surface Relief:

Moderate

Dispersion:

r > v

Chemistry of HydrochlorboriteHide

Mindat Formula:

Ca₄B₈O₁₅Cl₂ · 21H₂O

Element Weights:

Element	% weight
O	61.535 %
Ca	17.127 %
B	9.240 %
Cl	7.575 %
H	4.523 %

Calculated from ideal end-member formula.

Elements listed:

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

Crystallography of HydrochlorboriteHide

Crystal System:

Monoclinic

Class (H-M):

2/m - Prismatic

Cell Parameters:

a = 22.783(3) Å, b = 8.745(1) Å, c = 17.066(1) Å
β = 96.705(1)°

Ratio:

a:b:c = 2.605 : 1 : 1.952

Unit Cell V:

3,376.93 Å³ (Calculated from Unit Cell)

Morphology:

well-formed tabular crystals

Comment:

Space Group: I2/a

Crystallographic forms of HydrochlorboriteHide

Crystal Atlas:

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Click on an icon to view

Hydrochlorborite - Tabular {001}

3d models and HTML5 code kindly provided by www.smorf.nl.

Crystal StructureHide

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Unit Cell | Unit Cell Packed
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CIF File Best | x | y | z | a | b | c

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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)
0000683	Hydrochlorborite	Brown G E, Clark J R (1978) Crystal structure of hydrochlorborite, Ca2[B3O3(OH)4.OB(OH)3]Cl.7H2O, a seasonal evaporite mineral American Mineralogist 63 814-823		1978		0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Hydrochlorborite'
loop_
_publ_author_name
'Brown G E'
'Clark J R'
_journal_name_full 'American Mineralogist'
_journal_volume 63 
_journal_year 1978
_journal_page_first 814
_journal_page_last 823
_publ_section_title
;
 Crystal structure of hydrochlorborite, Ca2[B3O3(OH)4.OB(OH)3]Cl.7H2O,
 a seasonal evaporite mineral
;
_database_code_amcsd 0000683
_chemical_formula_sum 'Ca2 B4 Cl O18 H21'
_cell_length_a 22.783
_cell_length_b 8.745
_cell_length_c 17.066
_cell_angle_alpha 90
_cell_angle_beta 96.705
_cell_angle_gamma 90
_cell_volume 3376.929
_exptl_crystal_density_diffrn      1.841
_symmetry_space_group_name_H-M 'I 1 2/a 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,1/2+z'
  '1/2-x,y,-z'
  '-x,1/2+y,1/2-z'
  '1/2+x,-y,z'
  '+x,1/2-y,1/2+z'
  '-x,-y,-z'
  '1/2-x,1/2-y,1/2-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Ca1   0.03304   0.17170   0.16190 ?
Ca2   0.21377   0.05750   0.29560 ?
B1   0.15920   0.31500   0.19140 ?
B2   0.18970   0.46660   0.31660 ?
B3   0.08840   0.49020   0.24690 ?
B4  -0.01070   0.55960   0.17140 ?
Cl   0.13350   0.63560   0.00840 ?
O1   0.19390   0.32890   0.26930 ?
O2   0.10070   0.39040   0.18850 ?
O3   0.12930   0.53010   0.30760 ?
O4   0.03360   0.55560   0.24140 ?
O5   0.14750   0.14980   0.18030 ?
O6   0.19340   0.37640   0.13120 ?
O7   0.20560   0.43550   0.40120 ?
O8   0.23180   0.57930   0.28870 ?
O9  -0.05750   0.65340   0.19750 ?
O10  -0.03020   0.40010   0.15070 ?
O11   0.01100   0.63230   0.10210 ?
O12   0.05470   0.21420   0.02690 ?
O13   0.06100   0.91450   0.13540 ?
O14   0.05610   0.57590   0.42180 ?
O15   0.23790  -0.16010   0.39170 ?
O16   0.13580   0.85850   0.27670 ?
O17   0.16370   0.14880   0.40390 ?
O18   0.17450   0.99430   0.04430 ?
H1   0.15800   0.12000   0.14700   0.05066
H2   0.15900   0.43100   0.09600   0.07599
H3   0.24500   0.45100   0.41800   0.01267
H4   0.24200   0.66800   0.32800   0.01267
H5  -0.10300   0.67000   0.15300   0.11399
H6  -0.06100   0.37900   0.10200   0.07599
H7   0.05000   0.57000   0.08800   0.03800
H8   0.06400   0.15800   0.00300   0.13932
H9   0.03800   0.25700  -0.00300   0.03800
H10   0.03700   0.81300   0.11700   0.08866
H11   0.09800   0.87700   0.16000   0.06333
H12   0.08600   0.56400   0.36500   0.01267
H13   0.07900   0.63300   0.45600   0.06333
H14   0.21100  -0.17300   0.42300   0.06333
H15   0.27700  -0.18300   0.42200   0.02533
H16   0.14200   0.78500   0.27700   0.18998
H17   0.09300   0.84500   0.29400   0.10132
H18   0.15700   0.11100   0.44000   0.03800
H19   0.17400   0.24100   0.40900   0.05066
H20   0.18500   0.10400   0.00400   0.10132
H21   0.15800   0.90700   0.04600   0.17731
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 0.01945 0.01201 0.01252 -0.00200 0.00466 0.00075
Ca2 0.01764 0.01472 0.01179 0.00050 0.00447 0.00150
B1 0.01297 0.01201 0.00728 -0.00401 0.00194 0.00451
B2 0.02334 0.01705 0.01601 -0.00401 0.00583 0.00375
B3 0.01038 0.00000 0.02038 -0.00100 0.00389 0.00526
B4 0.01297 0.01705 0.01455 0.00100 0.00194 0.00075
Cl 0.03320 0.02635 0.02052 0.00501 0.00505 0.00150
O1 0.02075 0.01395 0.00728 0.00200 0.00000 -0.00075
O2 0.01297 0.01550 0.00146 0.00702 -0.00194 -0.00075
O3 0.01297 0.02635 0.02038 0.00702 -0.00583 -0.01051
O4 0.02075 0.01898 0.01892 0.00200 0.00583 -0.01126
O5 0.02594 0.01046 0.00728 -0.00301 0.00583 -0.00676
O6 0.02075 0.02092 0.01164 -0.00100 0.00777 0.00000
O7 0.02853 0.02092 0.00437 0.00100 0.00000 -0.00150
O8 0.02334 0.02247 0.01455 -0.00401 0.00777 -0.00150
O9 0.02075 0.02751 0.01892 -0.00601 0.00583 0.00976
O10 0.02075 0.01821 0.02474 -0.00100 0.00194 0.00601
O11 0.03113 0.01976 0.01164 -0.00301 0.00583 0.00451
O12 0.04928 0.03990 0.01892 0.00802 0.01360 0.00676
O13 0.03631 0.02015 0.03202 -0.00401 0.00389 -0.00676
O14 0.02594 0.03797 0.01746 0.00702 0.00777 -0.00225
O15 0.03113 0.02480 0.01892 -0.00100 0.00000 0.00150
O16 0.02853 0.01782 0.03347 0.00000 0.00000 0.00451
O17 0.04150 0.02402 0.01601 -0.00100 0.01360 0.00150
O18 0.03631 0.03913 0.01746 -0.00501 0.00777 -0.00601

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
8.48 Å	(100)
6.01 Å	(24)
3.604 Å	(9)
2.798 Å	(8)
2.825 Å	(7)
2.186 Å	(7)
8.18 Å	(6)

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Near-surface Processes
25 : Evaporites (prebiotic)

Type Occurrence of HydrochlorboriteHide

Co-Type Localities:

ⓘ Salar de Carcote, Ollagüe, El Loa Province, Antofagasta, Chile
ⓘ China

Place of Conservation of Type Material:

National Museum of Natural History, Washington, D.C., USA, 131036

Geological Setting of Type Material:

Qinghai-Xizang Plateau, Tibet
playa sediment

Associated Minerals at Type Locality:

Ulexite

Halite

Gypsum

Reference:

Qian Ziqiang, Chen Shuzhen, Ma Shinian, and Liu Xunjian (1965): Hydrochlorborite, a new hydrous chlor-borate mineral. Acta Geologica Sinica 45(2), 209-216 (in Chinese with English abstract).

Other Language Names for HydrochlorboriteHide

Dutch:Hydrochlorboriet

German:Hydrochlorborit

Russian:Гидрохлорборит

Simplified Chinese:多水氯硼钙石

Spanish:Hydrochlorborita

Traditional Chinese:多水氯硼鈣石

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.35	Uralborite	Ca₂[B₃O₃(OH)₅ · OB(OH)₃]	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/b

Other InformationHide

IR Spectrum:

Salar de Carcote material (Chukanov, 2014), [cm^-1]: 3525s, 3455s, 3260sh, 3070sh, 1667w, 1619, 1570, 1544, 1465sh, 1424, 1378s, 1365sh, 1240, 1170sh, 1124, 1078, 1009s, 967, 925, 904s, 822w, 764w, 703w, 644w, 603, 567, 510, 460

Notes:

Soluble in H2O.

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 HydrochlorboriteHide

mindat.org URL:

https://www.mindat.org/min-1970.html
Please feel free to link to this page.

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External Links:

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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 HydrochlorboriteHide

Reference List:

American Mineralogist 62, 147-150.

Chien Tzu-Chiang and Chen Su-Chien (1965): Brief note on preliminary results of a study of a new borate mineral - Hydrochlorborite: Ca4B8O15Cl2 * 22H2O. Scientia Sinica 14, 945-946 (in Russian).

Qian Ziqiang, Chen Shuzhen, Ma Shinian, and Liu Xunjian (1965): Hydrochlorborite, a new hydrous chlor-borate mineral. Acta Geologica Sinica 45(2), 209-216 (in Chinese with English abstract). - American Mineralogist 50, 2099 (abstract).

Qian Ziqiang, Chen Shuzhen, Ma Shinian, and Liu Xunjian (1965): Hydrochlorborite, a new hydrous chlor-borate mineral. Acta Geologica Sinica 45(2), 209-216 (in Chinese with English abstract).

Brown, Gordon E., Clark, Joan R. (1978) Crystal structure of hydrochlorborite, Ca2[B3O3(OH)4·OB(OH)3]Cl·7H2O, a seasonal evaporite mineral. American Mineralogist, 63 (9-10) 814-823

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

Chukanov, Nikita V. (2014) Springer Geochemistry/Mineralogy - Infrared spectra of mineral species. Springer Netherlands. doi:10.1007/978-94-007-7128-4

Localities for HydrochlorboriteHide

Showing 4 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.


Chile (TL)
Antofagasta El Loa Province Ollagüe ⓘ Salar de Carcote (TL)	AmMin. 62:147-150 (1977)

China (TL)

Qinghai Haixi Mongol and Tibetan Autonomous Prefecture ⓘ Mangnai City (Mangya Co.)	Shaoxiu (1991) +1 other reference

Turkey
Eskişehir Province Seyitgazi District Kirka ⓘ Sarıkaya B deposit	Koçak et al. (2016) +1 other reference

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Hydrochlorborite

About HydrochlorboriteHide

Unique IdentifiersHide

IMA Classification of HydrochlorboriteHide

Classification of HydrochlorboriteHide

Mineral SymbolsHide

Physical Properties of HydrochlorboriteHide

Optical Data of HydrochlorboriteHide

Chemistry of HydrochlorboriteHide

Crystallography of HydrochlorboriteHide

Crystallographic forms of HydrochlorboriteHide

Crystal StructureHide

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Type Occurrence of HydrochlorboriteHide

Other Language Names for HydrochlorboriteHide

Related Minerals - Strunz-mindat GroupingHide

Other InformationHide

Internet Links for HydrochlorboriteHide

References for HydrochlorboriteHide

Localities for HydrochlorboriteHide

Locality ListHide

Related Minerals - Strunz-mindat Grouping Hide