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Oxy-chromium-dravite

A valid IMA mineral species
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About Oxy-chromium-draviteHide

Formula:
NaCr3(Cr4Mg2)(Si6O18)(BO3)3(OH)3O
Colour:
Emerald green
Lustre:
Vitreous
Hardness:
7½
Specific Gravity:
3.299 (Calculated)
Crystal System:
Trigonal
Name:
For the mineral dravite and its oxygen and chromium contents.
The Cr analogue of vanadio-oxy-chromium-dravite. Oxy-chromium-dravite is related to chromium-dravite by the heterovalent substitution Cr3++O2− → Mg2++OH1−.


Unique IdentifiersHide

Mindat ID:
42725
Long-form identifier:
mindat:1:1:42725:8

IMA Classification of Oxy-chromium-draviteHide

Approved
IMA Formula:
NaCr3+3(Cr3+4Mg2)(Si6O18)(BO3)3(OH)3O
Approval year:
2012

Classification of Oxy-chromium-draviteHide

9.CK.05

9 : SILICATES (Germanates)
C : Cyclosilicates
K : [Si6O18]12- 6-membered single rings, with insular complex anions

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

Physical Properties of Oxy-chromium-draviteHide

Vitreous
Transparency:
Transparent
Colour:
Emerald green
Streak:
Green
Hardness:
7½ on Mohs scale
Hardness:
VHN50=1454.0 kg/mm2 - Vickers
Comment:
Mohs hardness approximately 7½ calculated from Vickers hardness.
Fracture:
Conchoidal
Density:
3.299 g/cm3 (Calculated)

Optical Data of Oxy-chromium-draviteHide

Type:
Uniaxial (-)
RI values:
nω = 1.765(5) nε = 1.715(6)
Max. Birefringence:
δ = 0.050
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
Pleochroism:
Visible
Comments:
pleochroic (O = dark green, E = yellow green) (in plane-polarized light)

Chemistry of Oxy-chromium-draviteHide

Mindat Formula:
NaCr3(Cr4Mg2)(Si6O18)(BO3)3(OH)3O
Element Weights:
Element% weight
O43.679 %
Cr32.053 %
Si14.840 %
Mg4.281 %
B2.856 %
Na2.025 %
H0.266 %

Calculated from ideal end-member formula.

Chemical AnalysisHide

Oxide wt%:
 12
SiO232.0 %32.9 %
TiO20.3 %0.3 %
Al2O36.3 %8.4 %
B2O39.3 %9.5 %
V2O30.3 %0.3 %
Cr2O335.1 %32.9 %
Fe2O30.3 %
MnO0.1 %
MgO8.4 %8.5 %
CaO1.1 %0.8 %
SrO0.4 %0.3 %
Na2O2.1 %2.2 %
K2O0.2 %0.2 %
F0.1 %0.1 %
H2O2.4 %2.5 %
FeO0.2 %
Total:98.4 %99.1 %
Sample references:
IDLocalityReferenceNotes
1American #1 Talc Mine, Balmat, Fowler, St. Lawrence County, New York, USAEPMA analysis of somewhat larger crystal; core. B2O3 and H2O calculated from stoichiometry.
2  "  "EPMA analysis of slightly lower-Cr rim composition of a different grain; B2O3 and H2O calculated from stoichiometry.

Crystallography of Oxy-chromium-draviteHide

Crystal System:
Trigonal
Class (H-M):
3m - Ditrigonal Pyramidal
Space Group:
R3m
Setting:
R3m
Cell Parameters:
a = 16.1121(3) Å, c = 7.3701(1) Å
Ratio:
a:c = 1 : 0.457
Unit Cell V:
1656.95 ų
Z:
3

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0019734Oxy-chromium-draviteBosi F, Reznitskii L, Skogby H (2012) Oxy-chromium-dravite, NaCr3(Cr4Mg2)(Si6O18)(BO3)3(OH)3O, a new mineral species of the tourmaline supergroup American Mineralogist 97 2024-20302012Pereval marble quarry, Sludyanka, Lake Baikal, Russia0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
6.480 Å(62)
4.634 Å(24)
4.270 Å(44)
4.014 Å(63)
3.542 Å(50)
3.005 Å(60)
2.600 Å(100)
2.063 Å(47)

Geological EnvironmentHide

Paragenetic Mode(s):
Geological Setting:
Metaquartzites

Type Occurrence of Oxy-chromium-draviteHide

General Appearance of Type Material:
elongated prisms terminated by a prominent pedion and small, minor pyramidal faces
Place of Conservation of Type Material:
Museum of Mineralogy, Earth Sciences Department, Sapienza University of Rome, Rome, Italy, catalogue number 33064
Geological Setting of Type Material:
chromphyllite-bearing quartzite and banded quartz-diopside rock
Associated Minerals at Type Locality:

Synonyms of Oxy-chromium-draviteHide

Other Language Names for Oxy-chromium-draviteHide

Relationship of Oxy-chromium-dravite to other SpeciesHide

Other Members of Tourmaline:
AdachiiteCaFe3Al6(Si5AlO18)(BO3)3(OH)3(OH)Trig. 3m : R3m
Alumino-oxy-rossmanite◻Al3Al6(Si5AlO18)(BO3)3(OH)3OTrig. 3m : R3m
BosiiteNaFe3+3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
Celleriite◻(Mn2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
Chromium-draviteNaMg3Cr3+6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
Chromo-alumino-povondraiteNaCr3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
DarrellhenryiteNa(Al2Li)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
DutrowiteNa(Fe2+2.5Ti0.5)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
ElbaiteNa(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
ErtliteNaAl3Al6(Si4B2O18)(BO3)3(OH)3OTrig. 3m : R3m
Ferro-bosiiteNaFe3+3(Al4Fe2+2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
FeruviteCaFe2+3(Al5Mg)(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
Fluor-buergeriteNaFe3+3Al6(Si6O18)(BO3)3O3FTrig. 3m : R3m
Fluor-draviteNaMg3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
Fluor-elbaiteNa(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
Fluor-liddicoatiteCa(Li2Al)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
Fluor-rossmanite◻(Al2Li)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m(32/m) : R3m
Fluor-schorlNaFe2+3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
Fluor-tsilaisiteNaMn2+3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
Fluor-uviteCaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
Foitite◻(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
LiddicoatiteCa(Li2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
LucchesiiteCaFe2+3 Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
Magnesio-dutrowiteNa(Mg2.5Ti0.5)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
Magnesio-foitite◻(Mg2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
Magnesio-lucchesiiteCaMg3Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
MaruyamaiteK(Al2Mg)(Al5Mg)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
OleniteNaAl3Al6(Si6O18)(BO3)3O3(OH)Trig. 3m : R3m
Oxy-draviteNa(Al2Mg)(Al5Mg)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
Oxy-foitite◻(Fe2+Al2)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m(32/m) : R3m
Oxy-schorlNa(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
Oxy-vanadium-draviteNaV3(V4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
PovondraiteNaFe3+3(Mg2Fe3+4)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
PrincivalleiteNa(Mn2Al)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
Rossmanite◻(LiAl2)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
SchorlNaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
TsilaisiteNaMn2+3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
'UM2000-64-SiO:BFeHKMg'(K,Na)Fe3+3(Mg2Fe3+4)Si6O18(BO3)3(OH)3O
'UM2008-52-SiO:AlBCaFFeHLiMgNa'(Ca,Na,◻)(Al,Li,Fe,Mg)3Al6[Si6O18](BO3)3(OH,O)3(F,O)
'Unnamed (F analogue of feruvite)'CaFe2+3(Al5Mg)(Si6O18)(BO3)3(OH)3F
'Unnamed (Mn2+-F-analogue of foitite)'◻(Mn2+2Al)Al6(Si6O18)(BO3)3(OH)3F ?
'Unnamed (Pb-analogue of Fluor-liddicoatite)'Pb(Li2Al)Al6(Si6O18)(BO3)3(OH)3F
UviteCaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
Vanadio-oxy-chromium-draviteNaV3(Cr4Mg2)(Si6O18)(BO3)3(OH)3O Trig. 3m : R3m
Vanadio-oxy-draviteNaV3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m

Common AssociatesHide

Associations Based on Photo Data:
1 photo of Oxy-chromium-dravite associated with Tremolite◻Ca2Mg5(Si8O22)(OH)2
1 photo of Oxy-chromium-dravite associated with QuartzSiO2

Related Minerals - Strunz-mindat GroupingHide

9.CK.AdachiiteCaFe3Al6(Si5AlO18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.Magnesio-dutrowiteNa(Mg2.5Ti0.5)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.DarrellhenryiteNa(Al2Li)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Fluor-schorlNaFe2+3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.PrincivalleiteNa(Mn2Al)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Alumino-oxy-rossmanite◻Al3Al6(Si5AlO18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.DutrowiteNa(Fe2+2.5Ti0.5)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Ferro-bosiiteNaFe3+3(Al4Fe2+2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.BosiiteNaFe3+3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Celleriite◻(Mn2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05FeruviteCaFe2+3(Al5Mg)(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Chromium-draviteNaMg3Cr3+6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-rossmanite◻(Al2Li)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m(32/m) : R3m
9.CK.05Oxy-schorlNa(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Fluor-elbaiteNa(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-uviteCaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05Foitite◻(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Vanadio-oxy-draviteNaV3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Fluor-buergeriteNaFe3+3Al6(Si6O18)(BO3)3O3FTrig. 3m : R3m
9.CK.05'Unnamed (F analogue of feruvite)'CaFe2+3(Al5Mg)(Si6O18)(BO3)3(OH)3F
9.CK.05ErtliteNaAl3Al6(Si4B2O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05TsilaisiteNaMn2+3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-liddicoatiteCa(Li2Al)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05UviteCaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05ElbaiteNa(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-tsilaisiteNaMn2+3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05Oxy-foitite◻(Fe2+Al2)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m(32/m) : R3m
9.CK.05LiddicoatiteCa(Li2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Vanadio-oxy-chromium-draviteNaV3(Cr4Mg2)(Si6O18)(BO3)3(OH)3O Trig. 3m : R3m
9.CK.05Rossmanite◻(LiAl2)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Oxy-vanadium-draviteNaV3(V4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05OleniteNaAl3Al6(Si6O18)(BO3)3O3(OH)Trig. 3m : R3m
9.CK.05'UM2000-64-SiO:BFeHKMg'(K,Na)Fe3+3(Mg2Fe3+4)Si6O18(BO3)3(OH)3O
9.CK.05Magnesio-lucchesiiteCaMg3Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05PovondraiteNaFe3+3(Mg2Fe3+4)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05LucchesiiteCaFe2+3 Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Chromo-alumino-povondraiteNaCr3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Fluor-draviteNaMg3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05Oxy-draviteNa(Al2Mg)(Al5Mg)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05'Luinaite-(OH)'NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)Mon. m : Bm
9.CK.05SchorlNaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Magnesio-foitite◻(Mg2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05MaruyamaiteK(Al2Mg)(Al5Mg)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.10Abenakiite-(Ce)Na26Ce6(Si6O18)(PO4)6(CO3)6(SO2)OTrig. 3 : R3
9.CK.15ScawtiteCa7(Si3O9)2CO3 · 2H2OMon. 2/m
9.CK.20Thorosteenstrupine(Ca,Th,Mn)3Si4O11F · 6H2O
9.CK.20Steenstrupine-(Ce)Na14Mn2+2Fe3+2Ce6Zr(Si6O18)2(PO4)6(PO3OH)(OH)2 · 2H2OTrig. 3m(32/m) : R3m

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 Oxy-chromium-draviteHide

References for Oxy-chromium-draviteHide

Localities for Oxy-chromium-draviteHide

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.
Russia (TL)
 
  • Irkutsk Oblast
    • Slyudyansky District
      • Slyudyanka
Williams et al. (2012) +1 other reference
USA
 
  • New York
    • St. Lawrence County
      • Fowler
        • Balmat
Frank K. Mazdab collection (thin section FKM-276) +1 other reference
 
and/or  
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