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Borocookeite

A valid IMA mineral species
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About BorocookeiteHide

Formula:
(LiAl4◻)[BSi3O10](OH)8
Also given as Li1+3xAl4-x(BSi3O10)(OH)8, with x ≤ 0.33.
Colour:
Light grey with a pinkish or yellow hue
Lustre:
Greasy
Hardness:
3
Specific Gravity:
2.62
Crystal System:
Monoclinic
Member of:
Name:
Named in allusion to the composition and its relationship to cookeite. Al is replaced by B relative to cookeite.
The B analogue of cookeite.


Unique IdentifiersHide

Mindat ID:
28988
Long-form identifier:
mindat:1:1:28988:9

IMA Classification of BorocookeiteHide

Classification of BorocookeiteHide

9.EC.55

9 : SILICATES (Germanates)
E : Phyllosilicates
C : Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets

Mineral SymbolsHide

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.

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

Greasy
Transparency:
Translucent
Colour:
Light grey with a pinkish or yellow hue
Streak:
Light pinkish-grey
Hardness:
Cleavage:
Perfect
perfect (001)
Parting:
none
Fracture:
None observed
Comment:
Tenacity: Not elastic.
Density:
2.62(1) g/cm3 (Measured)    2.69(1) g/cm3 (Calculated)

Optical Data of BorocookeiteHide

Type:
Biaxial
RI values:
nα = 1.574(2) nβ = 1.58(2) nγ = 1.591(2)
2V:
Calculated: 72°
Max. Birefringence:
δ = 0.017
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.

Surface Relief:
Moderate (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.
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.
Dispersion:
not determined

Chemistry of BorocookeiteHide

Mindat Formula:
(LiAl4◻)[BSi3O10](OH)8

Also given as Li1+3xAl4-x(BSi3O10)(OH)8, with x ≤ 0.33.
Element Weights:
Element% weight
O56.916 %
Al21.330 %
Si16.652 %
B2.137 %
H1.594 %
Li1.372 %

Calculated from ideal end-member formula.
O
Al
Si
B
H
Li

Crystallography of BorocookeiteHide

Crystal System:
Monoclinic
Class (H-M):
m - Domatic
Space Group:
Bb
Setting:
Cc
Cell Parameters:
a = 5.11 Å, b = 8.856 Å, c = 14.08 Å
β = 96.93°
Ratio:
a:b:c = 0.577 : 1 : 1.59
Unit Cell V:
632.52 ų (Calculated from Unit Cell)
Z:
4
Comment:
Space Group: Probably Cc by analogy with cookeite.

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 4b: Highly evolved igneous rocks>3.0
34 : Complex granite pegmatites

Type Occurrence of BorocookeiteHide

General Appearance of Type Material:
Dense, massive crypto-flaky aggregate or thin crusts and snow-like coatings on crystals of quartz, tourmaline, and feldspars from miarolitic cavities.
Place of Conservation of Type Material:
A.E. Fersman Mineralogical Museum, Russian Academy of Science, Moscow, Russia (2522/1).
Geological Setting of Type Material:
A late-stage pocket mineral in the Sosedka and Mokhovaya pegmatite veins.
Associated Minerals at Type Locality:

Synonyms of BorocookeiteHide

Other Language Names for BorocookeiteHide

Relationship of Borocookeite to other SpeciesHide

Member of:
Other Members of Chlorite Group:
BaileychloreZn5Al(AlSi3O10)(OH)8Tric. 1
ChamositeFe2+5Al(AlSi3O10)(OH)8Mon. 2/m : B2/m
ClinochloreMg5Al(AlSi3O10)(OH)8Mon. 2/m : B2/m
Cookeite(LiAl4◻)[AlSi3O10](OH)8Mon. 2/m
DonbassiteAl4.33(AlSi3O10)(OH)8Mon. 2 : B2
FranklinfurnaceiteCa2Fe3+Mn2+3Mn3+(Zn2Si2O10)(OH)8Mon. 2 : B2
GlagoleviteNa(Mg,Al)6(AlSi3O10)(OH,O)8Tric. 1 : P1
GonyeriteMn2+5Fe3+(Fe3+Si3O10)(OH)8Orth.
NimiteNi5Al(AlSi3O10)(OH)8Mon. 2/m : B2/m
PennantiteMn2+5Al(AlSi3O10)(OH)8Tric.
SudoiteMg2Al3(AlSi3O10)(OH)8Mon. 2/m : B2/m
VakhrushevaiteMg5Cr(AlSi3O10)(OH)8Tric. 1

Common AssociatesHide

Associations Based on Photo Data:
2 photos of Borocookeite associated with Lepidolite

Related Minerals - Strunz-mindat GroupingHide

9.EC.MeifuiteKFe6(Si7Al)O19(OH)4Cl2Tric. 1 : P1
9.EC.BalestraiteKLi2V5+Si4O12Mon. 2 : B2
9.EC.05TalcMg3Si4O10(OH)2Tric. 1 : P1
9.EC.05MinnesotaiteFe2+3Si4O10(OH)2Tric. 1 : P1
9.EC.05WillemseiteNi3Si4O10(OH)2Mon.
9.EC.9.EC.VoloshiniteRb(LiAl1.50.5)(Al0.5Si3.5)O10F2Mon. 2/m : B2/b
9.EC.10FluorluanshiweiiteKLiAl1.5(Si3.5Al0.5)O10F2Mon. 2/m : B2/m
9.EC.10GarmiteCsLiMg2(Si4O10)F2Mon.
9.EC.10GorbunoviteCsLi2(Ti,Fe)Si4O10(F,OH,O)2Mon.
9.EC.10FerripyrophylliteFe3+Si2O5(OH)Mon. 2/m
9.EC.10ManganiceladoniteK(MgMn3+◻)(Si4O10)(OH)2Mon.
9.EC.10LuanshiweiiteKLiAl1.5(Si3.5Al0.5)O10(OH)2Mon. 2/m : B2/b
9.EC.10PyrophylliteAl2Si4O10(OH)2Tric. 1
9.EC.15ParagoniteNaAl2(AlSi3O10)(OH)2Mon.
9.EC.15FerroaluminoceladoniteK(Fe2+Al◻)(Si4O10)(OH)2Mon. 2/m : B2/m
9.EC.15NanpingiteCsAl2(AlSi3O10)(OH,F)2Mon. 2/m : B2/b
9.EC.15FerroceladoniteK(Fe2+Fe3+◻)(Si4O10)(OH)2Mon. 2/m : B2/m
9.EC.15GanteriteBa0.5(Na,K)0.5Al2(Si2.5Al1.5)O10(OH)2Mon. 2/m : B2/b
9.EC.15KreiteriteCsLi2Fe3+(Si4O10)F2Mon.
9.EC.15RoscoeliteKV3+2(AlSi3O10)(OH)2Mon. 2/m : B2/b
9.EC.15AluminoceladoniteK(MgAl◻)(Si4O10)(OH)2Mon. 2/m : B2/m
9.EC.15Tobelite(NH4)Al2(AlSi3O10)(OH)2Mon. 2/m : B2/m
9.EC.15TainioliteKLiMg2(Si4O10)F2Mon. 2/m : B2/m
9.EC.15CeladoniteK(MgFe3+◻)(Si4O10)(OH)2Mon. 2/m : B2/m
9.EC.15ChromceladoniteK(MgCr◻)(Si4O10)(OH)2Mon. 2 : B2
9.EC.15MontdoriteKFe2+1.5Mn2+0.5Mg0.5Si4O10(F,OH)2Mon. 2/m : B2/m
9.EC.15ChromphylliteKCr2(AlSi3O10)(OH)2Mon. 2/m : B2/b
9.EC.15BoromuscoviteKAl2(BSi3O10)(OH)2Mon. 2/m
9.EC.15'UM1988-22-SiO:AlCaFFeHKLiMg'KLiMgAl2Si3O10F2Mon.
9.EC.15Chernykhite(Ba,Na)(V3+,Al,Mg)2((Si,Al)4O10)(OH)2Mon.
9.EC.15MuscoviteKAl2(AlSi3O10)(OH)2Mon. 2/m : B2/b
9.EC.20MasutomiliteK(LiAlMn2+)[AlSi3O10]F2Mon. 2 : B2
9.EC.20OxyphlogopiteK(Mg,Ti,Fe)3[(Si,Al)4O10](O,F)2Mon. 2/m : B2/m
9.EC.20'Chloroferrokinoshitalite'(Ba,K)(Fe2+,Mg)3(Al2Si2O10)(Cl,OH,F)2
9.EC.20SiderophylliteKFe2+2Al(Al2Si2O10)(OH)2Mon.
9.EC.20SokolovaiteCsLi2Al(Si4O10)F2Mon.
9.EC.20HendricksiteKZn3(Si3Al)O10(OH)2Mon. 2/m : B2/m
9.EC.20TetraferriphlogopiteKMg3(Si3Fe3+)O10(OH)2Mon. 2/m : B2/m
9.EC.20FluoranniteKFe2+3(Si3Al)O10F2Mon. 2/m : B2/m
9.EC.20AspidoliteNaMg3(AlSi3O10)(OH)2Mon. 2/m : B2/m
9.EC.20Suhailite(NH4)Fe2+3(AlSi3O10)(OH)2Mon. 2/m : B2/m
9.EC.20EphesiteNaLiAl2(Al2Si2O10)(OH)2Tric. 1 : P1
9.EC.20NorrishiteKLiMn3+2(Si4O10)O2Mon. 2/m : B2/m
9.EC.20PhlogopiteKMg3(AlSi3O10)(OH)2Mon. 2/m : B2/m
9.EC.20YangzhumingiteKMg2.5(Si4O10)F2Mon. 2/m : B2/m
9.EC.20OrloviteKLi2Ti(Si4O10)OFMon. 2 : B2
9.EC.20TetraferrianniteKFe2+3(Si3Fe3+)O10(OH)2Mon. 2/m : B2/m
9.EC.20ShirokshiniteK(NaMg2)(Si4O10)F2Mon. 2/m : B2/m
9.EC.20TrilithioniteK(Li1.5Al1.5)(AlSi3O10)(F,OH)2Mon. 2/m : B2/b
9.EC.20PolylithioniteKLi2Al(Si4O10)(F,OH)2Mon. 2/m : B2/b
9.EC.20ShirozuliteKMn2+3(Si3Al)O10(OH)2Mon. 2/m : B2/m
9.EC.20PreiswerkiteNaMg2Al(Al2Si2O10)(OH)2Mon. 2/m : B2/b
9.EC.20FluorophlogopiteKMg3(Si3Al)O10F2Mon. 2/m : B2/m
9.EC.20Wonesite(Na,K,◻)(Mg,Fe,Al)6(Si,Al)8O20(OH,F)4Mon. 2/m : B2/m
9.EC.20'UM2004-49-SiO:AlCsFHKLi'(Cs,K)(Al,Li)2.6((Si,Al)4O10)(F,OH)2
9.EC.20FluorotetraferriphlogopiteKMg3(Fe3+Si3O10)F2Mon. 2/m : B2/m
9.EC.20AnniteKFe2+3(AlSi3O10)(OH)2Mon. 2/m : B2/m
9.EC.20EastoniteKMg2Al(Al2Si2O10)(OH)2Mon.
9.EC.22'Pimelite'Ni3Si4O10(OH)2 · 4H2OHex.
9.EC.30MargariteCaAl2(Al2Si2O10)(OH)2Mon. 2/m : B2/b
9.EC.35Kinoshitalite(Ba,K)(Mg,Mn2+,Al)3(Al2Si2O10)(OH)2Mon. 2/m : B2/m
9.EC.35Ferrokinoshitalite(Ba,K)(Fe2+,Mg)3(Al2Si2O10)(OH,F)2Mon. 2/m : B2/m
9.EC.35ClintoniteCaAlMg2(SiAl3O10)(OH)2Mon. 2/m : B2/m
9.EC.35Oxykinoshitalite(Ba,K)(Mg,Ti,Fe3+,Fe2+)3((Si,Al)4O10)(O,OH,F)2Mon. 2/m : B2/m
9.EC.35FluorokinoshitaliteBaMg3(Al2Si2O10)F2Mon. 2/m : B2/m
9.EC.35BityiteCaLiAl2(AlBeSi2O10)(OH)2Mon. 2/m : B2/b
9.EC.35Anandite(Ba,K)(Fe2+,Mg)3((Si,Al,Fe)4O10)(S,OH)2Mon. 2/m : B2/b
9.EC.40Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2OMon. 2/m : B2/m
9.EC.40Beidellite(Na,Ca0.5)0.3Al2((Si,Al)4O10)(OH)2 · nH2OMon. 2/m : B2/m
9.EC.40VolkonskoiteCa0.3(Cr,Mg,Fe)2((Si,Al)4O10)(OH)2 · 4H2OMon.
9.EC.40NontroniteNa0.3Fe2((Si,Al)4O10)(OH)2 · nH2OMon. 2/m : B2/m
9.EC.40Kurumsakite(Zn,Ni,Cu)8Al8V5+2Si5O35 · 27H2O (?)Orth.
9.EC.40Yakhontovite(Ca,Na)0.5(Cu,Fe,Mg)2(Si4O10)(OH)2 · 3H2OMon.
9.EC.45SwineforditeLi(Al,Li,Mg)3((Si,Al)4O10)2(OH,F)4 · nH2OMon. 2/m : B2/m
9.EC.45HectoriteNa0.3(Mg,Li)3(Si4O10)(F,OH)2Mon. 2/m : B2/m
9.EC.45ZincsiliteZn3Si4O10(OH)2 · 4H2O (?)Mon.
9.EC.45HanjiangiteBa2CaV3+Al(H2AlSi3O12)(CO3)2FMon. 2 : B2
9.EC.45SpadaiteMgSiO2(OH)2 · H2O (?)
9.EC.45FerrosaponiteCa0.3(Fe2+,Mg,Fe3+)3((Si,Al)4O10)(OH)2 · 4H2OMon.
9.EC.45Stevensite(Ca,Na)xMg3-x(Si4O10)(OH)2Mon.
9.EC.45SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2OMon.
9.EC.45SauconiteNa0.3Zn3((Si,Al)4O10)(OH)2 · 4H2OMon.
9.EC.50VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2OMon. 2/m
9.EC.52'Tarasovite'near NaKAl11Si13O40(OH)9 · 3H2O
9.EC.55ClinochloreMg5Al(AlSi3O10)(OH)8Mon. 2/m : B2/m
9.EC.55FranklinfurnaceiteCa2Fe3+Mn2+3Mn3+(Zn2Si2O10)(OH)8Mon. 2 : B2
9.EC.55PennantiteMn2+5Al(AlSi3O10)(OH)8Tric.
9.EC.55VakhrushevaiteMg5Cr(AlSi3O10)(OH)8Tric. 1
9.EC.55NimiteNi5Al(AlSi3O10)(OH)8Mon. 2/m : B2/m
9.EC.55Cookeite(LiAl4◻)[AlSi3O10](OH)8Mon. 2/m
9.EC.55GonyeriteMn2+5Fe3+(Fe3+Si3O10)(OH)8Orth.
9.EC.55ChamositeFe2+5Al(AlSi3O10)(OH)8Mon. 2/m : B2/m
9.EC.55'Orthochamosite'(Fe2+,Mg,Fe3+)5Al(AlSi3O10)(OH,O)8
9.EC.55BaileychloreZn5Al(AlSi3O10)(OH)8Tric. 1
9.EC.55SudoiteMg2Al3(AlSi3O10)(OH)8Mon. 2/m : B2/m
9.EC.55GlagoleviteNa(Mg,Al)6(AlSi3O10)(OH,O)8Tric. 1 : P1
9.EC.55DonbassiteAl4.33(AlSi3O10)(OH)8Mon. 2 : B2
9.EC.60DozyiteMg7Al2(Al2Si4O15)(OH)12Mon.
9.EC.60Rectorite(Na,Ca)Al4((Si,Al)8O20)(OH)4 · 2H2OMon.
9.EC.60Corrensite(Mg,Fe)9((Si,Al)8O20)(OH)10 · nH2OOrth.
9.EC.60AliettiteCa0.2Mg6((Si,Al)8O20)(OH)4 · 4H2OMon.
9.EC.60Karpinskite(Ni,Mg)2Si2O5(OH)2 (?)Mon.
9.EC.60LunijianlaiteLi0.7Al6.2(AlSi7O20)(OH,O)10Mon.
9.EC.60TosuditeNa0.5(Al,Mg)6((Si,Al)8O18)(OH)12 · 5H2OMon. 2 : B2
9.EC.60HydrobiotiteK(Mg,Fe2+)6((Si,Al)8O20)(OH)4 · nH2OMon. 2/m : B2/m
9.EC.60Saliotite(Li,Na)Al3(AlSi3O10)(OH)5Mon. 2/m : B2/m
9.EC.60KulkeiteMg8Al(AlSi7O20)(OH)10Mon.
9.EC.60BrinrobertsiteNa0.3Al4(Si4O10)2(OH)4 · 3.5 H2OMon.
9.EC.65Macaulayite(Fe,Al)24Si4O43(OH)2Mon.
9.EC.70BurckhardtitePb2(Fe3+Te6+)[AlSi3O8]O6Trig. 3m(32/m) : P31m
9.EC.75Niksergievite(Ba,Ca)2Al3(AlSi3O10)(CO3)(OH)6 · nH2OMon.
9.EC.75Ferrisurite(Pb,Ca)2.4Fe3+2(Si4O10)(CO3)1.7(OH)3 · nH2OMon.
9.EC.75Surite(Pb,Ca)3(Al,Fe2+,Mg)2((Si,Al)4O10)(CO3)2(OH)2Mon. 2 : P21
9.EC.80KegelitePb8Al4(Si8O20)(SO4)2(CO3)4(OH)8Mon.

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 BorocookeiteHide

References for BorocookeiteHide

Localities for BorocookeiteHide

Showing 5 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.
Brazil
 
  • Minas Gerais
    • Conselheiro Pena
Phillip Betancourt
  • Rio Grande do Norte
    • Parelhas
Novák et al. (2011)
Russia
 
  • Zabaykalsky Krai
    • Krasnochikoysky District
      • Krasnyi Chikoy
Thomas et al. (2012)
Zagorsky et al. (2003)
Zagorsky et al. (2003) +2 other references
 
and/or  
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