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Penikisite

A valid IMA mineral species
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About PenikisiteHide

Formula:
Ba(Mg,Fe2+,Ca)2Al2(PO4)3(OH)3
Colour:
Blue to green
Lustre:
Vitreous
Hardness:
4
Specific Gravity:
3.79
Crystal System:
Monoclinic
Name:
After Gunar Penikis (1936-1979), geophysicist and prospector of Ross River, Yukon Territory, one of the early explorers (1974-1975) in partnership with A. Kulan of the Rapid Creek area localities. It is pronounced PĔNĪ•KĬSAIT.
Kulanite-Penikisite Series.

It has the same general appearance as kulanite and both species can be found in the same crystal. The penikisite zones are generally near the edges of mixed kulanite-penikisite crystals. These zones do not follow the crystal outlines. The penikisite zones are paler and the kulanite zones are darker.


Unique IdentifiersHide

Mindat ID:
3148
Long-form identifier:
mindat:1:1:3148:2

IMA Classification of PenikisiteHide

Classification of PenikisiteHide

8.BH.20

8 : PHOSPHATES, ARSENATES, VANADATES
B : Phosphates, etc., with additional anions, without H2O
H : With medium-sized and large cations, (OH,etc.):RO4 = 1:1
41.9.1.2

41 : ANHYDROUS PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
9 : (AB)5(XO4)3Zq
19.5.11

19 : Phosphates
5 : Phosphates of Sr and Ba

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

Physical Properties of PenikisiteHide

Vitreous
Transparency:
Transparent, Translucent
Colour:
Blue to green
Streak:
Very pale green to white
Hardness:
Cleavage:
Distinct/Good
Two fair to good cleavages {O10} and {100}
Density:
3.79(2) g/cm3 (Measured)    3.82 g/cm3 (Calculated)
Comment:
Measured with a Berman balance

Optical Data of PenikisiteHide

Type:
Biaxial (+)
RI values:
nα = 1.684(2) nβ = 1.688(2) nγ = 1.705(2)
2V:
Measured: 52° to 56°, Calculated: 54°
Max. Birefringence:
δ = 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.

Surface Relief:
Very 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.
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:
very strong asymmetrical dispersion with dispersion of the optic axes r>>y.
Optical Extinction:
X ~ Y > Z
Pleochroism:
Visible
Comments:
X grass-green, Y blue-green, Z pale pink
Comments:
b~Y and c:Z=-6°, although b:Y ranges from 0° to 19°

Chemistry of PenikisiteHide

Mindat Formula:
Ba(Mg,Fe2+,Ca)2Al2(PO4)3(OH)3
Element Weights:
Element% weight
O41.677 %
Ba23.848 %
P16.137 %
Al9.371 %
Mg8.442 %
H0.525 %

Calculated from ideal end-member formula.
O
Ba
P
Al
Mg
H

Crystallography of PenikisiteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/m
Setting:
P21/m
Cell Parameters:
a = 8.9577(4) Å, b = 12.0150(5) Å, c = 4.9070(2) Å
β = 100.505(2)°, γ = °
Ratio:
a:b:c = 0.746 : 1 : 0.408
Unit Cell V:
519.37 ų
Z:
2

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0019754PenikisiteBowman M G, Downs R T, Yang H (2013) Penikisite, BaMg2Al2(PO4)3(OH)3, isostructural with bjarebyite Acta Crystallographica E69 i4-i52013Mayo Mining District, Yukon Territory, Canada0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
8.81 Å(60)
3.094 Å(100)
3.028 Å(60)
2.915 Å(80)
2.684 Å(60)
2.6494 Å(70)

Geological EnvironmentHide

Paragenetic Mode(s):

Type Occurrence of PenikisiteHide

General Appearance of Type Material:
The same as kulanite. Well formed blue to green crystals.
Place of Conservation of Type Material:
The Royal Ontario Museum, Toronto, Ontario, Canada (ROM No. M34172).
Associated Minerals at Type Locality:

Synonyms of PenikisiteHide

Other Language Names for PenikisiteHide

German:Penikisit
Spanish:Penikisita

Relationship of Penikisite to other SpeciesHide

Other Members of Bjarebyite Group:
Bjarebyite(Ba,Sr)(Mn2+,Fe2+,Mg)2Al2(PO4)3(OH)3Mon. 2/m : P21/m
JohntomaiteBaFe2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
KulaniteBa(Fe2+,Mn2+,Mg)2(Al,Fe3+)2(PO4)3(OH)3Mon. 2/m : P21/m
Nigelcookite PbFe2+2V3+2(PO4)3(OH)3Mon. 2/m : P21/m
PerloffiteBa(Mn2+,Fe2+)2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
Plumbojohntomaite PbFe2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
PlumboperloffitePbMn2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
StrontioperloffiteSrMn2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
Forms a series with:

Common AssociatesHide

Associations Based on Photo Data:
3 photos of Penikisite associated with KulaniteBa(Fe2+,Mn2+,Mg)2(Al,Fe3+)2(PO4)3(OH)3
1 photo of Penikisite associated with QuartzSiO2

Related Minerals - Strunz-mindat GroupingHide

8.BH.PeterchiniteZn3Zn2(OH)6As[O3(OH)3]Mon. 2/m : B2/m
8.BH.ReznitskyiteCaMg(VO4)FMon. 2/m : B2/b
8.BH.PlumbogottlobitePbMg(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.CuprozheshengitePb4CuZn2(AsO4)2(PO4)2(OH)2Tric. 1 : P1
8.BH.ZheshengitePb4ZnZn2(AsO4)2(PO4)2(OH)2Tric. 1 : P1
8.BH.CrimsonitePbFe3+2(PO4)2(OH)2Orth. mmm(2/m2/m2/m) : Cccm
8.BH.05ThadeuiteCa(Mg,Fe2+)3(PO4)2(OH,F)2Orth. 222 : C2221
8.BH.10PanasqueiraiteCaMg(PO4)(OH)Mon.
8.BH.10IsokiteCaMg(PO4)FMon. 2/m : B2/b
8.BH.10LacroixiteNaAl(PO4)FMon. 2/m : B2/b
8.BH.10ArsenatrotitaniteNaTi(AsO4)OMon. 2/m : B2/b
8.BH.10MaxwelliteNaFe3+(AsO4)FMon. 2/m : P2/m
8.BH.10DurangiteNaAl(AsO4)FMon. 2/m : B2/b
8.BH.10KononoviteNaMg(SO4)FMon. 2/m : B2/b
8.BH.15DrugmanitePb2Fe3+(PO4)(PO3OH)(OH)2Mon. 2/m : P21/b
8.BH.20Nigelcookite PbFe2+2V3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20Plumbojohntomaite PbFe2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20CirroliteCa3Al2(PO4)3(OH)3 (?)
8.BH.20PerloffiteBa(Mn2+,Fe2+)2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20Bjarebyite Group
8.BH.20StrontioperloffiteSrMn2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20PlumboperloffitePbMn2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20JohntomaiteBaFe2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20Bjarebyite(Ba,Sr)(Mn2+,Fe2+,Mg)2Al2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20KulaniteBa(Fe2+,Mn2+,Mg)2(Al,Fe3+)2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.25BertossaiteLi2CaAl4(PO4)4(OH)4Orth. mmm(2/m2/m2/m)
8.BH.25NatropalermoiteNa2SrAl4(PO4)4(OH)4Orth. mmm(2/m2/m2/m)
8.BH.25PalermoiteLi2SrAl4(PO4)4(OH)4Orth. mmm(2/m2/m2/m)
8.BH.30SewarditeCaFe3+2(AsO4)2(OH)2Orth. mmm(2/m2/m2/m) : Cccm
8.BH.30CarminitePbFe3+2(AsO4)2(OH)2Orth. mmm(2/m2/m2/m) : Cccm
8.BH.35AdeliteCaMg(AsO4)(OH)Orth. 222 : P212121
8.BH.35DuftitePbCu(AsO4)(OH)Orth. 222 : P212121
8.BH.35CobaltaustiniteCaCo(AsO4)(OH)Orth. 222 : P212121
8.BH.35NickelaustiniteCaNi(AsO4)(OH)Orth. 222 : P212121
8.BH.35GabrielsonitePbFe3+(As3+O3)OOrth. mm2 : Pmc21
8.BH.35ConichalciteCaCu(AsO4)(OH)Orth. 222 : P212121
8.BH.35ArsendescloizitePbZn(AsO4)(OH)Orth. 222 : P212121
8.BH.35'Duftite-alpha'PbCu(AsO4)(OH)
8.BH.35GottlobiteCaMg(VO4)(OH)Orth. 222 : P212121
8.BH.35AustiniteCaZn(AsO4)(OH)Orth. 222 : P212121
8.BH.35HermannroseiteCaCu(PO4)(OH)Orth. 222 : P212121
8.BH.35TangeiteCaCu(VO4)(OH)Orth. 222 : P212121
8.BH.40ČechitePbFe2+(VO4)(OH)Orth. mmm(2/m2/m2/m)
8.BH.40Khorixasite(Bi0.670.33)Cu(VO4)(OH)Mon. 2/m : P2/m
8.BH.40MottramitePbCu(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.40DescloizitePbZn(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.40PyrobelonitePbMn2+(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.45BayldonitePbCu3(AsO4)2(OH)2Mon. 2/m : B2/b
8.BH.45VésigniéiteBaCu3(VO4)2(OH)2Mon. 2/m : B2/m
8.BH.50PaganoiteNiBi(AsO4)OTric. 1 : P1
8.BH.55JagoweriteBaAl2(PO4)2(OH)2Tric.
8.BH.55HarrisoniteCa(Fe2+,Mg)6(PO4)2(SiO4)2Trig. 3m(32/m) : R3m
8.BH.60AttakoliteCaMn2+Al4(SiO3OH)(PO4)3(OH)4Mon. 2/m : B2/m
8.BH.65LeningraditePbCu3(VO4)2ClOrth. mmm(2/m2/m2/m) : Ibam
8.BH.70KatiarsiteKTiO(AsO4)Orth. mm2 : Pna21
8.BH.70YurgensoniteK2SnTiO2(AsO4)2Orth. mm2 : Pna21
8.BH.75MelanarsiteK3Cu7Fe3+O4(AsO4)4Mon. 2/m : B2/b
8.BH.80EvseeviteNa2Mg(AsO4)FOrth. mmm(2/m2/m2/m) : Pbcn
8.BH.80MoraskoiteNa2Mg(PO4)FOrth. mmm(2/m2/m2/m) : Pbcn
8.BH.85PiccoliiteNaCaMn3+2(AsO4)2O(OH)Orth. mmm(2/m2/m2/m) : Pbcm

Fluorescence of PenikisiteHide

Not fluorescent under short-wave and long-wave ultraviolet light

Other InformationHide

Thermal Behaviour:
A weight loss of 3.88% and an endothermic peak at 71O C.
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 PenikisiteHide

References for PenikisiteHide

Localities for PenikisiteHide

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.
Canada
 
  • Yukon
    • Dawson mining district
Robinson et al. (1992)
150-152. +3 other references
    • Mayo mining district
M. Mauthner (collection)
University of British Columbia (Pacific Museum of the Earth) +2 other references
 
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