Bulgakite
A valid IMA mineral species
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About Bulgakite
Formula:
Li2CaFe2+7Ti2[Si4O12]2O2(OH)4O(H2O)2
Colour:
Brownish orange
Lustre:
Vitreous
Hardness:
3
Specific Gravity:
3.30 - 3.326
Crystal System:
Triclinic
Member of:
Name:
Named after Lev Vasil'evich Bulgak (Лев Васильевич Булгак) (b. 1955), Russian mineralogist, gemologist, and discoverer of several new minerals. He worked at the A. E. Fersman Mineralogical Museum (1975-2003).
Unique Identifiers
Mindat ID:
46415
Long-form identifier:
mindat:1:1:46415:2
IMA Classification of Bulgakite
Approved
IMA Formula:
Li2(Ca,Na)Fe2+7Ti4+2(Si4O12)2O2(OH)4(O,F)(H2O)2
Approval year:
2014
First published:
2016
Type description reference:
Agakhanov, Atali A., Pautov, Leonid A., Sokolova, Elena, Abdu, Yassir A., Karpenko, Vladimir Y. (2016) Two Astrophyllite-Supergroup Minerals: Bulgakite, A New Mineral From the Darai-Pioz Alkaline Massif, Tajikistan and Revision of the Crystal Structure and Chemical Formula of Nalivkinite. The Canadian Mineralogist, 54 (1) 33-48 doi:10.3749/canmin.1500085
Classification of Bulgakite
9.DC.
9 : SILICATES (Germanates)
D : Inosilicates
C : Inosilicates with branched 2-periodic single chains; Si2O6 + 2SiO3 Si4O12
9 : SILICATES (Germanates)
D : Inosilicates
C : Inosilicates with branched 2-periodic single chains; Si2O6 + 2SiO3 Si4O12
Mineral Symbols
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.
Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Bgk | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
| Bgk | Warr (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 Bulgakite
Vitreous
Transparency:
Transparent, Translucent
Colour:
Brownish orange
Streak:
Pale brown streak
Hardness:
3 on Mohs scale
Hardness:
VHN100=204 - Vickers
Tenacity:
Brittle
Cleavage:
Perfect
Perfect parallel to {001} and moderate parallel to {010}
Perfect parallel to {001} and moderate parallel to {010}
Fracture:
Hackly
Density:
3.30 - 3.326 g/cm3 (Measured) 3.326 g/cm3 (Calculated)
Optical Data of Bulgakite
Type:
Biaxial (+)
RI values:
nα = 1.695(3) nβ = 1.711(2) nγ = 1.750(3)
2V:
Measured: 70° (5), Calculated: 67°
Max. Birefringence:
δ = 0.055
Based on recorded range of RI values above.
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.
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:
Very High (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).
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.
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:
Strong: r > v
Pleochroism:
Visible
Comments:
X = intensive reddish brown, Y = light brown, Z = greenish
light brown
light brown
Chemistry of Bulgakite
Mindat Formula:
Li2CaFe2+7Ti2[Si4O12]2O2(OH)4O(H2O)2
Element Weights:
Crystallography of Bulgakite
Crystal System:
Triclinic
Class (H-M):
1 - Pinacoidal
Space Group:
P1
Cell Parameters:
a = 5.374(1) Å, b = 11.965(2) Å, c = 11.654(3) Å
α = 113.457(8)°, β = 94.533(8)°, γ = 103.084(10)°
α = 113.457(8)°, β = 94.533(8)°, γ = 103.084(10)°
Ratio:
a:b:c = 0.449 : 1 : 0.974
Unit Cell V:
657.5 ų
Z:
1
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 10.54 Å | (100) |
| 3.50 Å | (100) |
| 2.783 Å | (90) |
| 2.647 Å | (55) |
| 2.578 Å | (100) |
| 1.760 Å | (52) |
| 1.660 Å | (46) |
| 1.576 Å | (68) |
Reference:
Agakhanov, Atali A., Pautov, Leonid A., Sokolova, Elena, Abdu, Yassir A., Karpenko, Vladimir Y. (2016) Two Astrophyllite-Supergroup Minerals: Bulgakite, A New Mineral From the Darai-Pioz Alkaline Massif, Tajikistan and Revision of the Crystal Structure and Chemical Formula of Nalivkinite. The Canadian Mineralogist, 54 (1) 33-48 doi:10.3749/canmin.1500085
Comments:
From Type Description.
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Stage 4b: Highly evolved igneous rocks | >3.0 |
| 35 : Ultra-alkali and agpaitic igneous rocks |
Type Occurrence of Bulgakite
Place of Conservation of Type Material:
Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, registration number 4572/1
Geological Setting of Type Material:
Fenitized amphibole–quartz–feldspar rock from a glacial morraine
Associated Minerals at Type Locality:
Reference:
Agakhanov, Atali A., Pautov, Leonid A., Sokolova, Elena, Abdu, Yassir A., Karpenko, Vladimir Y. (2016) Two Astrophyllite-Supergroup Minerals: Bulgakite, A New Mineral From the Darai-Pioz Alkaline Massif, Tajikistan and Revision of the Crystal Structure and Chemical Formula of Nalivkinite. The Canadian Mineralogist, 54 (1) 33-48 doi:10.3749/canmin.1500085
Synonyms of Bulgakite
Other Language Names for Bulgakite
Relationship of Bulgakite to other Species
Member of:
Other Members of Astrophyllite Group:
| Astrophyllite | K2NaFe2+7Ti2[Si4O12]2O2(OH)4F | Tric. 1 : P1 |
| 'Hydroastrophyllite' | [H3O]+2CaFe2+7Ti2[Si4O12]2O2(OH)4O | Tric. |
| Nalivkinite | Li2NaFe2+7Ti2[Si4O12]2O2(OH)4F(H2O)2 | Tric. 1 : P1 |
| Niobophyllite | K2NaFe2+7(NbTi)[Si4O12]2O2(OH)4O | Tric. |
| Tarbagataite | (K◻)CaFe2+7Ti2[Si4O12]2O2(OH)4(OH) | Tric. 1 : P1 |
| Zircophyllite | K2NaFe2+7Zr2[Si4O12]2O2(OH)4F | Tric. |
Related Minerals - Strunz-mindat Grouping
| 9.DC.05 | Devitoite | Ba4Ba2Fe2+7Fe3+2[Si4O12]2[PO4]2[CO3]O2(OH)4◻2 |
| 9.DC.05 | Zircophyllite | K2NaFe2+7Zr2[Si4O12]2O2(OH)4F |
| 9.DC.05 | Nalivkinite | Li2NaFe2+7Ti2[Si4O12]2O2(OH)4F(H2O)2 |
| 9.DC.05 | Sveinbergeite | (H2O)2[Ca(H2O)](Fe2+6Fe3+)Ti2[Si4O12]2O2(OH)4[(OH)(H2O)] |
| 9.DC.05 | Niobophyllite | K2NaFe2+7(NbTi)[Si4O12]2O2(OH)4O |
| 9.DC.05 | Heyerdahlite | Na2NaMn2+7Ti2[Si4O12]2O2(OH)4F(H2O)2 |
| 9.DC.05 | Tarbagataite | (K◻)CaFe2+7Ti2[Si4O12]2O2(OH)4(OH) |
| 9.DC.05 | Astrophyllite | K2NaFe2+7Ti2[Si4O12]2O2(OH)4F |
| 9.DC.05 | 'Hydroastrophyllite' | [H3O]+2CaFe2+7Ti2[Si4O12]2O2(OH)4O |
| 9.DC.05 | Lobanovite | K2Na(Fe2+4Mg2Na)Ti2[Si4O12]2O2(OH)4◻ |
| 9.DC.05 | Niobokupletskite | K2NaMn2+7(NbTi)[Si4O12]2O2(OH)4O |
| 9.DC.05 | Kupletskite-(Cs) | Cs2NaMn2+7Ti2[Si4O12]2O2(OH)4F |
| 9.DC.05 | Kupletskite | K2NaMn2+7Ti2[Si4O12]2O2(OH)4F |
| 9.DC.05 | Laverovite | K2NaMn2+7Zr2[Si4O12]2O2(OH)4F |
Fluorescence of Bulgakite
None
Other Information
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 Bulgakite
mindat.org URL:
https://www.mindat.org/min-46415.html
Please feel free to link to this page.
Please feel free to link to this page.
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Mineral Dealers:
References for Bulgakite
Reference List:
Williams, P. A., Hatert, F., Pasero, M., Mills, S. J. (2014) IMA Commission on New Minerals, Nomenclature and Classification (CNMNC), CNMNC Newsletter No. 22. Mineralogical Magazine, 78 (5) 1241-1248 doi:10.1180/minmag.2014.078.5.10
Agakhanov, Atali A., Pautov, Leonid A., Sokolova, Elena, Abdu, Yassir A., Karpenko, Vladimir Y. (2016) Two Astrophyllite-Supergroup Minerals: Bulgakite, A New Mineral From the Darai-Pioz Alkaline Massif, Tajikistan and Revision of the Crystal Structure and Chemical Formula of Nalivkinite. The Canadian Mineralogist, 54 (1) 33-48 doi:10.3749/canmin.1500085
Localities for Bulgakite
Showing 1 localities.
symbol to view information about a locality.
The Locality List
- 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).
All localities listed without proper references should be considered as questionable.
Tajikistan (TL) | |
| Agakhanov et al. (2016) |
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Dara-i-Pioz Massif, Districts of Republican Subordination, Tajikistan