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Chlorellestadite

A valid IMA mineral species
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02028210017360473767197.jpg
Chlorellestadite, etc.

NW slope, Shadil-Khokh volcano, Kel’ volcanic area, South Ossetia, Georgia
01098490017271922026785.jpg
Chlorellestadite

NW slope, Shadil-Khokh volcano, Kel’ volcanic area, South Ossetia, Georgia
02028210017360473767197.jpg
Chlorellestadite, etc.

NW slope, Shadil-Khokh volcano, Kel’ volcanic area, South Ossetia, Georgia
01098490017271922026785.jpg
Chlorellestadite

NW slope, Shadil-Khokh volcano, Kel’ volcanic area, South Ossetia, Georgia
08589820017360473773803.jpg
Chlorellestadite, etc.

NW slope, Shadil-Khokh volcano, Kel’ volcanic area, South Ossetia, Georgia
01098490017271922026785.jpg
Chlorellestadite

NW slope, Shadil-Khokh volcano, Kel’ volcanic area, South Ossetia, Georgia
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About ChlorellestaditeHide

Formula:
Ca5(SiO4)1.5(SO4)1.5Cl
Colour:
White, tinged with blue or green
Lustre:
Vitreous
Hardness:
4½
Specific Gravity:
3.091 (Calculated)
Crystal System:
Hexagonal
Name:
In allusion to its composition, being the chlorine-dominant analogue of hydroxylellestadite and fluorellestadite. The name ellestadite (sensu lato) was first introduced by McConnell (1937) and named in honour of Dr. Ruben B. Ellestad (1900-1993), American analytical chemist of Minneapolis.
The Cl-end member of the ellestadite group. It forms in xenoliths of calcium-silicate composition when they are exposed to Cl-bearing volcanic exhalations at about 1,000 °C under low pressure conditions.


Unique IdentifiersHide

Mindat ID:
1015
Long-form identifier:
mindat:1:1:1015:9

IMA Classification of ChlorellestaditeHide

IMA status:
Approved
IMA Formula:
Ca10(SiO4)3(SO4)3Cl2
Approval year:
2017
First published:
2018
Approval history:
The name has been used of a mineral with the ideal end-member formula Ca10(SiO4)3(SO4)3Cl2. It was assumed not to exist and therefore to be discredited (Pasero et al., 2010), although a synthetic equivalent has been synthesised.
Approved by IMA in 2017.
Type description reference:
Środek, Dorota, Galuskina, Irina O., Galuskin, Evgeny, Dulski, Mateusz, Książek, Maria, Kusz, Joachim, Gazeev, Viktor (2018) Chlorellestadite, Ca5(SiO4)1.5(SO4)1.5Cl, a new ellestadite- group mineral from the Shadil-Khokh volcano, South Ossetia. Mineralogy and Petrology, 112 (5) 743-752 doi:10.1007/s00710-018-0571-1

Classification of ChlorellestaditeHide

Strunz-mindat (2026):
9.AH.25

9 : SILICATES (Germanates)
A : Nesosilicates
H : Nesosilicates with CO3, SO4, PO4, etc.
Dana 8th ed.:
52.4.9.5

52 : NESOSILICATES Insular SiO4 Groups and O,OH,F,H2O
4 : Insular SiO4 Groups and O, OH, F, and H2O with cations in [6] and/or >[6] coordination
Hey's CIM Ref.:
17.10.20

17 : Silicates Containing other Anions
10 : Silicates with sulphate, molybdate or tungstate

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

Physical Properties of ChlorellestaditeHide

Lustre:
Vitreous
Transparency:
Transparent
Colour:
White, tinged with blue or green
Streak:
White
Hardness:
4½ on Mohs scale
Hardness:
VHN100=443 - Vickers
Tenacity:
Brittle
Cleavage:
Poor/Indistinct
Parallel to elongation
Fracture:
Irregular/Uneven
Density:
3.091 g/cm3 (Calculated)

Optical Data of ChlorellestaditeHide

Type:
Uniaxial (-)
RI values:
nω = 1.664(3) nε = 1.659(3)
Birefringence:
0.005
Max. Birefringence:
δ = 0.005
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
Optical Extinction:
Parallel
Pleochroism:
Non-pleochroic

Chemistry of ChlorellestaditeHide

Mindat Formula:
Ca5(SiO4)1.5(SO4)1.5Cl
Element Weights:
Element% weight
Ca38.681 %
O37.060 %
S9.284 %
Si8.132 %
Cl6.843 %

Calculated from ideal end-member formula.
Elements listed:
Ca, Cl, O, S, Si - search for minerals with similar chemistry
Common Impurities:
Al,Fe,Mn,Mg,C

Crystallography of ChlorellestaditeHide

Crystal System:
Hexagonal
Class (H-M):
6/m - Dipyramidal
Space Group:
P63/m
Cell Parameters:
a = 9.6002(2) Å, c = 6.8692(2) Å
Ratio:
a:c = 1 : 0.716
Unit Cell V:
548.27 ų
Z:
2
Morphology:
Elongate crystals

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0015527ChlorellestaditeSaint-Jean S J, Hansen S (2005) Nonstoichiometry in chlorellestadite Solid State Sciences 7 97-1022005synthetic0293
0015526ChlorellestaditeSaint-Jean S J, Hansen S (2005) Nonstoichiometry in chlorellestadite Solid State Sciences 7 97-1022005synthetic0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
8.24 Å(8)
5.31 Å(4)
4.12 Å(8)
3.92 Å(6)
3.45 Å(40)
3.18 Å(6)
3.11 Å(18)
2.835 Å(95)
2.796 Å(40)
2.746 Å(100)
2.645 Å(25)
2.554 Å(4)
2.312 Å(2)
2.284 Å(40)
2.168 Å(4)
2.070 Å(2)
2.009 Å(2)
1.958 Å(30)
1.909 Å(15)
1.850 Å(25)
1.823 Å(10)
1.797 Å(10)
1.768 Å(8)
1.725 Å(8)
1.658 Å(4)
1.621 Å(4)
1.603 Å(4)
1.557 Å(4)
1.545 Å(2)
1.518 Å(4)
1.510 Å(2)
1.486 Å(6)
1.461 Å(8)
1.446 Å(8)
1.417 Å(2)
Comments:
ICDD 25-167 Phosphatian chlorellestadite.

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere<0.6
50 : Coal and/or oil shale minerals<0.36
51 : Pyrometamorphic minerals (see also #54 and #56)<0.36
Stage 10b: Anthropogenic minerals<10 Ka
54 : Coal and other mine fire minerals (see also #51 and #56)

Type Occurrence of ChlorellestaditeHide

Type Locality:
ⓘ NW slope, Shadil-Khokh volcano, Kel’ volcanic area, South Ossetia, Georgia
General Appearance of Type Material:
Inhomogeneous, porous, elongate grains up to 0.2-0.3 mm in length
Place of Conservation of Type Material:
Type material is deposited in the collections of the Fersman Mineralogical Museum, Leninskiy pr., 18/k2, 115162 Moscow, Russia, catalogue number 4975/1
Empirical Formula of Type Material:
Ca4.99Na0.01(SiO4)1.51(SO4)1.46(PO4)0.03(Cl0.61OH0.21F0.11)Σ= 0.93
Geological Setting of Type Material:
Calcium-silicate xenolith in rhyodacite lava
Associated Minerals at Type Locality:
ChlormayeniteJasmunditeLarniteOldhamiteRondorfite
SpurriteSrebrodolskite
Reference:
Środek, Dorota, Galuskina, Irina O., Galuskin, Evgeny, Dulski, Mateusz, Książek, Maria, Kusz, Joachim, Gazeev, Viktor (2018) Chlorellestadite, Ca5(SiO4)1.5(SO4)1.5Cl, a new ellestadite- group mineral from the Shadil-Khokh volcano, South Ossetia. Mineralogy and Petrology, 112 (5) 743-752 doi:10.1007/s00710-018-0571-1

Synonyms of ChlorellestaditeHide

Other Language Names for ChlorellestaditeHide

Relationship of Chlorellestadite to other SpeciesHide

Member of:
Ellestadite Group > Apatite Supergroup
Other Members of Ellestadite Group:
FluorellestaditeCa5(SiO4)1.5(SO4)1.5FHex. 6/m : P63/m
HydroxylellestaditeCa5(SiO4)1.5(SO4)1.5(OH)Hex. 6/mmm(6/m2/m2/m) : P63/mcm
MattheddleitePb5(SiO4)1.5(SO4)1.5(Cl,OH)Hex. 6/m : P63/m

Common AssociatesHide

Associations Based on Photo Data:
1 photo of Chlorellestadite associated with RondorfiteCa8Mg(SiO4)4Cl2
1 photo of Chlorellestadite associated with SpurriteCa5(SiO4)2(CO3)
1 photo of Chlorellestadite associated with LarniteCa2SiO4
1 photo of Chlorellestadite associated with HydrocalumiteCa4Al2(OH)12(Cl,CO3,OH)2 · 4H2O

Related Minerals - Strunz-mindat GroupingHide

9.AH.Fluorbritholite-(Nd)Ca2Nd3(SiO4)3FHex. 6/m : P63/m
9.AH.05Iimoriite-(Y)Y2[SiO4][CO3]Tric. 1 : P1
9.AH.10Tundrite-(Ce)Na2Ce2Ti(SiO4)(CO3)2O2Tric. 1 : P1
9.AH.10Tundrite-(Nd)Na2(Nd,Ce)2Ti(SiO4)(CO3)2O2
9.AH.15GaluskiniteCa7(SiO4)3(CO3) Mon. 2/m : P21/b
9.AH.15SpurriteCa5(SiO4)2(CO3)Mon. 2/m : P21/b
9.AH.20TernesiteCa5(SiO4)2(SO4)Orth. mmm(2/m2/m2/m) : Pnma
9.AH.20SilicocarnotiteCa5[(SiO4)(PO4)](PO4)Orth. mmm(2/m2/m2/m) : Pnma
9.AH.25Britholite-(Ce)(Ce,Ca)5(SiO4)3OHHex. 6/m : P63/m
9.AH.25Britholite-(Y)(Y,Ca)5(SiO4)3OHHex. 6/m : P63/m
9.AH.25MattheddleitePb5(SiO4)1.5(SO4)1.5(Cl,OH)Hex. 6/m : P63/m
9.AH.25Fluorbritholite-(Ce)(Ce,Ca)5(SiO4)3FHex. 6/m : P63/m
9.AH.25FluorellestaditeCa5(SiO4)1.5(SO4)1.5FHex. 6/m : P63/m
9.AH.25Fluorbritholite-(La)Ca2La3(SiO4)3FHex. 6/m : P63/m
9.AH.25Fluorbritholite-(Y)(Y,Ca)5(SiO4)3FHex. 6/m : P63/m
9.AH.25HydroxylellestaditeCa5(SiO4)1.5(SO4)1.5(OH)Hex. 6/mmm(6/m2/m2/m) : P63/mcm
9.AH.25'Calciobritholite'(Ca,Y)5(SiO4,PO4)3(OH)
9.AH.25'Britholite-(La)'Ca2(La,Ce,Ca)3(SiO4,PO4)3(OH,F)
9.AH.25Tritomite-(Ce)Ce5(SiO4,BO4)3(OH,O)
9.AH.25Tritomite-(Y)Y5(SiO4,BO4)3(O,OH,F)
9.AH.25Fluorcalciobritholite(Ca,REE)5(SiO4,PO4)3FHex. 6/m : P63/m
9.AH.35DargaiteBaCa12(SiO4)4(SO4)2O3Trig. 3m(32/m) : R3m
9.AH.35NabimusaiteKCa12(SiO4)4(SO4)2O2FTrig. 3m(32/m) : R3m
9.AH.40StracheriteBaCa6(SiO4)2[(PO4)(CO3)]FTrig. 3m(32/m) : R3m
9.AH.40ZadoviteBaCa6[(SiO4)(PO4)](PO4)2FTrig. 3m : R3m
9.AH.40GazeeviteBaCa6(SiO4)2(SO4)2OTrig. 3m(32/m) : R3m
9.AH.45FlamiteCa8-x(Na,K)x(SiO4)4-x(PO4)xOrth. mm2
9.AH.50ByzantieviteBa5(Ca,REE,Y)22(Ti,Nb)18(SiO4)4[(PO4),(SiO4)]4(BO3)9O22[(OH),F]43(H2O)1.5Trig. 3 : R3
9.AH.55Greenwoodite(Ba,V3+O)2V3+9(Fe3+,Fe2+)2Si2O22Trig. 3m(32/m) : P3m1
9.AH.60Kihlmanite-(Ce)Ce2TiO2(SiO4)(HCO3)2(H2O)Tric. 1 : P1
9.AH.65TsangpoiteCa5(PO4)2(SiO4)Hex.
9.AH.70'Enalite'(Th,REE,Al) [(PO4),(SiO4),(OH)]Tet.

Fluorescence of ChlorellestaditeHide

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 ChlorellestaditeHide

References for ChlorellestaditeHide

Localities for ChlorellestaditeHide

Showing 6 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.
Cuba
 
  • Cienfuegos Province
Stanislav M. Alexandrov analytical data
Czech Republic
 
  • South Moravian Region
    • Brno-Country District
      • Oslavany
Sejkora J et al. (1999) +1 other reference
Georgia (TL)
 
  • South Ossetia
    • Kel’ volcanic area
      • Shadil-Khokh volcano
Hålenius et al. (2017) +3 other references
Romania
 
  • Hunedoara County
    • Boșorod
Onac et al. (2002) +1 other reference
Russia
 
  • Chelyabinsk Oblast
Sharygin (2015)
USA
 
  • California
    • Riverside County
      • Jurupa Valley
        • Crestmore
[micromounts@yahoogroups.com] +2 other references
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