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Harkerite

A valid IMA mineral species - grandfathered
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00605060017271923596217.jpg
Harkerite

Kombat Mine, Kombat, Otavi Constituency, Otjozondjupa Region, Namibia
04216160017360473968413.jpg
Harkerite, etc.

Tazheranskii Massif, Russia
03287230017360473974687.jpg
Harkerite

Ariccia, Metropolitan City of Rome Capital, Lazio, Italy
00605060017271923596217.jpg
Harkerite

Kombat Mine, Kombat, Otavi Constituency, Otjozondjupa Region, Namibia
01134410017271923622727.jpg
Harkerite, etc.

Tazheranskii Massif, Russia
03287230017360473974687.jpg
Harkerite

Ariccia, Metropolitan City of Rome Capital, Lazio, Italy
00605060017271923596217.jpg
Harkerite

Kombat Mine, Kombat, Otavi Constituency, Otjozondjupa Region, Namibia
01134410017271923622727.jpg
Harkerite, etc.

Tazheranskii Massif, Russia
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About HarkeriteHide

02060860017271923784399.jpg
Alfred Harker
Formula:
Ca48Mg16[AlSi4O15(OH)]4(BO3)16(CO3)16 · 2(H2O,HCl)
Formerly given as Ca12Mg4Al(BO3)3(SiO4)4(CO3)5 · H2O

Evans et al. (2018) report the formula as ~Ca48Mg16[AlSi4(O,OH)16]4(BO3)16(CO3)16(HCl,H2O)2

Finally redefined to the formula given above.
Colour:
White; also tannish brown
Lustre:
Sub-Vitreous, Waxy, Dull
Specific Gravity:
2.96
Crystal System:
Trigonal
Name:
Named in 1948 by Cecil Edgar Tilley for systematic petrologist Alfred Harker (19 February 1859, Hull, Yorkshire, UK - 28 July 1939) of the Scottish Geological Survey.
White to tannish brown pseudo-octahedral crystals.

Structurally related to sakhaite with which it forms a solid solution (Sakhaite-Harkerite solid solution).

Compare UM1990-59-SiO:AlBCHMg.

Seems to be (in particular) a hydrochloride (chlorhydrate).


Unique IdentifiersHide

Mindat ID:
1819
Long-form identifier:
mindat:1:1:1819:3

Similar NamesHide

ParkeriteA valid IMA mineral species - grandfatheredNi3(Bi,Pb)2S2

IMA Classification of HarkeriteHide

IMA status:
Approved, 'Grandfathered' (first described prior to 1959)
IMA status notes:
Redefined by the IMA
IMA Formula:
Ca48Mg16[AlSi4O15(OH)]4(BO3)16(CO3)16·2(H2O,HCl)
First published:
1951
Approval history:
Final redefinitions due to data from the Newsletter #60 (Miyawaki et al. 2021).
Type description reference:
Tilley, C. E. (1951) The zoned contact-skarns of the Broadford area, Skye: a study of boron-fluorine metasomatism in dolomites. Mineralogical Magazine and Journal of the Mineralogical Society, 29 (214) 621-666 doi:10.1180/minmag.1951.029.214.01

Classification of HarkeriteHide

Strunz-mindat (2026):
6.AB.70

6 : BORATES
A : Monoborates
B : BO3, with additional anions; 1(D) + OH, etc.
Dana 8th ed.:
17.1.9.1

17 : COMPOUND CARBONATES
1 : Miscellaneous
Hey's CIM Ref.:
17.5.16

17 : Silicates Containing other Anions
5 : Borosilicates

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

Physical Properties of HarkeriteHide

Lustre:
Sub-Vitreous, Waxy, Dull
Transparency:
Translucent
Colour:
White; also tannish brown
Streak:
White
Tenacity:
Brittle
Cleavage:
None Observed
Fracture:
Irregular/Uneven
Density:
2.96 g/cm3 (Measured)    3.00 g/cm3 (Calculated)

Optical Data of HarkeriteHide

Type:
Uniaxial
RI values:
nα = 1.649 - 1.653 nβ = 1.649 - 1.653
Surface Relief:
Unknown
Optical Extinction:
May be anomalously biaxial
Pleochroism:
Non-pleochroic

Chemistry of HarkeriteHide

Mindat Formula:
Ca48Mg16[AlSi4O15(OH)]4(BO3)16(CO3)16 · 2(H2O,HCl)

Formerly given as Ca12Mg4Al(BO3)3(SiO4)4(CO3)5 · H2O

Evans et al. (2018) report the formula as ~Ca48Mg16[AlSi4(O,OH)16]4(BO3)16(CO3)16(HCl,H2O)2

Finally redefined to the formula given above.
Element Weights:
Element% weight
O44.420 %
Ca32.969 %
Si7.701 %
Mg6.665 %
C3.293 %
B2.964 %
Al1.850 %
H0.138 %

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

Chemical AnalysisHide

Oxide wt%:
 1
SiO212.74 %
B2O39.20 %
Al2O32.51 %
FeO0.87 %
MgO11.32 %
CaO46.31 %
CO213.9 %
Cl1.26 %
H2O1.92 %
Total:100.03 %
Empirical formulas:
Sample IDEmpirical Formula
1Ca47.12Mg16.02[Al0.70Fe3+0.17Si3.03O15(OH)]4(B0.94O3)16(C1.13O3)16 · 2(H2O,HCl)
Sample references:
IDLocalityReferenceNotes
1Camas Malag, Torrin, Broadford, Isle of Skye, Eilean á Chèo, Highland, Scotland, UK
Davies, W. O.; Machin, M. P. (1970) Isomorphous replacements in harkerite and the relation of sakhaite to harkerite. The Canadian Mineralogist, 10 (4). p.689-695.
Wet chemical analysis by I.V. Nikitina (1966) from a skarn sample. Formula normalized to 158 (O,OH,Cl) by Davis and Machin.

Crystallography of HarkeriteHide

Crystal System:
Trigonal
Class (H-M):
3m(32/m) - Hexagonal Scalenohedral
Space Group:
R3m
Cell Parameters:
a = 18.131 Å
α = 33.46°
Unit Cell V:
1,613.62 ų (Calculated from Unit Cell)
Morphology:
Pseudo-octahedrons.
Comment:
Pseudo-isometric Fd3m. Hexagonal cell-parameters: a = 10.439, c = 51.303 Å (Z =3).

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0000564HarkeriteGiuseppetti G, Mazzi F, Tadini C (1977) The crystal structure of harkerite American Mineralogist 62 263-27219770293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
5.22 Å(70)
3.39 Å(60)
3.01 Å(60)
2.84 Å(60)
2.61 Å(100)
2.13 Å(80)
1.84 Å(90)
1.51 Å(70)
Comments:
10-0465

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
High-? alteration and/or metamorphism
31 : Thermally altered carbonate, phosphate, and iron formations
Geological Setting:
High temperature contact metamorphism assemblages.

Type Occurrence of HarkeriteHide

Other Language Names for HarkeriteHide

Dutch:Harkeriet
German:Harkerit
Simplified Chinese:碳硼硅钙镁石
Spanish:Harkerita

Relationship of Harkerite to other SpeciesHide

Common AssociatesHide

Associations Based on Photo Data:
11 photos of Harkerite associated with CalciteCaCO3
6 photos of Harkerite associated with MonticelliteCaMg(SiO4)
5 photos of Harkerite associated with PhlogopiteKMg3(AlSi3O10)(OH)2
3 photos of Harkerite associated with VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
3 photos of Harkerite associated with CuspidineCa8(Si2O7)2F4
3 photos of Harkerite associated with MagnetiteFe2+Fe3+2O4
2 photos of Harkerite associated with MalachiteCu2(CO3)(OH)2
2 photos of Harkerite associated with HydromagnesiteMg5(CO3)4(OH)2 · 4H2O
1 photo of Harkerite associated with TobermoriteCa5Si6O17 · 5H2O
1 photo of Harkerite associated with DatoliteCaB(SiO4)(OH)

Related Minerals - Strunz-mindat GroupingHide

6.AB.ChubaroviteKZn2(BO3)Cl2Trig. 32 : R32
6.AB.Rhabdoborite-(Mo)Mg12Mo6+1.33O6(BO3)6F2Hex. 6 : P63
6.AB.05HambergiteBe2(BO3)(OH)Orth. mmm(2/m2/m2/m) : Pbca
6.AB.10BerboriteBe2(BO3)(OH) · H2OTrig.
6.AB.15JeremejeviteAl6(BO3)5(F,OH)3Hex. 6/m : P63/m
6.AB.20YuanfuliiteMg(Fe3+,Al)O(BO3)Orth. mmm(2/m2/m2/m) : Pnma
6.AB.20Warwickite(Mg,Ti,Fe,Al)2O(BO3)Orth. mmm(2/m2/m2/m) : Pnma
6.AB.25Karlite(Mg,Al)6.5(BO3)3(OH)4(◻,Cl)0.5Orth. 222 : P21212
6.AB.30MarinaiteCu2Fe3+O2(BO3)Mon. 2/m : P21/b
6.AB.30SavelievaiteMg2Cr3+O2(BO3)Orth. mmm(2/m2/m2/m) : Pbam
6.AB.30FredrikssoniteMg2Mn3+O2(BO3)Orth. mmm(2/m2/m2/m) : Pbam
6.AB.30VonseniteFe2+2Fe3+(BO3)O2Orth. mmm(2/m2/m2/m) : Pbam
6.AB.30LudwigiteMg2Fe3+(BO3)O2Orth. mmm(2/m2/m2/m) : Pbam
6.AB.30Azoproite(Mg,Fe2+)2(Fe3+,Ti,Mg)(BO3)O2Orth. mmm(2/m2/m2/m) : Pbam
6.AB.30BonaccorditeNi2Fe3+(BO3)O2Orth. mmm(2/m2/m2/m) : Pbam
6.AB.35FolvikiteSb5+Mn3+(Mg,Mn2+)10O8(BO3)4Mon. 2 : P2
6.AB.35Pinakiolite(Mg,Mn2+)2Mn3+(BO3)O2Mon. 2/m : B2/m
6.AB.40Takéuchiite(Mg,Mn2+)2(Mn3+,Fe3+)(BO3)O2Orth. mmm(2/m2/m2/m) : Pnnm
6.AB.40BlatteriteSb5+3(Mn3+,Fe3+)9(Mn2+,Mg)35(BO3)16O32Orth. mmm(2/m2/m2/m) : Pnnm
6.AB.40Orthopinakiolite(Mg,Mn2+)2Mn3+(BO3)O2Orth. mmm(2/m2/m2/m) : Pnnm
6.AB.40ChestermaniteMg2(Fe3+,Mn3+,Al,Sb3+)(BO3)O2Orth. mmm(2/m2/m2/m)
6.AB.45Aluminomagnesiohulsite(Mg,Fe2+)2(Al,Mg,Sn)(BO3)O2Mon. 2/m : P2/m
6.AB.45HulsiteFe2+2Fe3+O2(BO3)Mon. 2/m : P2/m
6.AB.45MagnesiohulsiteMg2Fe3+O2(BO3)Mon. 2/m : P2/m
6.AB.50FluoboriteMg3(BO3)(F,OH)3Hex. 6/m : P63/m
6.AB.50HydroxylboriteMg3(BO3)(OH)3Hex. 6/m : P63/m
6.AB.55ShabyniteMg5(BO3)(OH)5(Cl,OH)2 · 4H2OMon.
6.AB.55WightmaniteMg5(BO3)O(OH)5 · 2H2OMon. 2/m
6.AB.60GaudefroyiteCa4Mn3+2-3(BO3)3(CO3)(O,OH)3Hex.
6.AB.65SakhaiteCa48Mg16(BO3)32(CO3)16 · 2(H2O,HCl)Iso. m3m(4/m32/m) : Fd3m
6.AB.75Pertsevite-(F)Mg2(BO3)(F,OH)Orth. mm2 : Pna21
6.AB.75Pertsevite-(OH)Mg2(BO3)(OH)Orth. mmm(2/m2/m2/m) : Pnma
6.AB.80JacquesdietrichiteCu2(H2BO3)(OH)3Orth. mmm(2/m2/m2/m) : Pmna
6.AB.85Rhabdoborite-(V)Mg12(V5+,Mo6+,W6+)1.5O6{[BO3]6-x[(P,As)O4]xF2-x} (x < 1)Hex. 6 : P63
6.AB.85Rhabdoborite-(W)Mg12(W6+,V5+)1.5O6{[BO3]6-x[(P,As)O4]xF2-x} Hex. 6 : P63
6.AB.85PainiteCaZrAl9(BO3)O15Hex. 6/m : P63/m
6.AB.90Mengxianminite(Ca,Na)2Sn2(Mg,Fe)3Al8[(BO3)(BeO4)O6]2Orth. mm2 : Fdd2

Fluorescence of HarkeriteHide

In UV light:
Red fluorescence in shortwave UV.

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 HarkeriteHide

References for HarkeriteHide

Reference List:
Grew, E.S., Yates, M.G., Adams, P., Kirkby, R., Wiedenbeck, M. (1999) Harkerite from the Crestmore Quarry, Riverside County, California and Cascade Slide, Adirondack Mountains, New York: A contrast in metamorphic pressure. The Canadian Mineralogist: 37: 277-296.
Tilley, C. E. (1948) Dolomite Contact Skarns of the Broadford Area, Skye: A Preliminary Note. Geological Magazine, 85 (4) 213-216 doi:10.1017/s0016756800073118
Tilley, C. E. (1951) The zoned contact-skarns of the Broadford area, Skye: a study of boron-fluorine metasomatism in dolomites. Mineralogical Magazine and Journal of the Mineralogical Society, 29 (214) 621-666 doi:10.1180/minmag.1951.029.214.01
Fleischer, M. (1952) New mineral names. American Mineralogist, 37 (3-4). 359-362
Ostrovskaya I.V., Pertsev N.N., Nikitina I.B. (1966) Sakhaite, a new carbonate-borate of calcium and magnesium. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva: 95(2): 193-202.
Fleischer, Michael (1966) New Mineral Names. American Mineralogist, 51 (11-12) 1815-1820
Davies, W. O.; Machin, M. P. (1970) Isomorphous replacements in harkerite and the relation of sakhaite to harkerite. The Canadian Mineralogist, 10 (4). p.689-695.
Barbieri, M, Cozzupoli, D, Federico, M, Fornaseri, M, Merlino, S, Orlandi, P, Tolomeo, L (1977) Harkerite from the Alban Hills, Italy. Lithos, 10 (2) 133-141 doi:10.1016/0024-4937(77)90040-8
Giuseppetti, Giuseppe, Mazzi, Fiorenzo, Tadini, Carla (1977) The crystal structure of harkerite. American Mineralogist, 62 (3-4) 263-272
Koneva, A.A., Uschapovskaya, Z.F. (1991) On harkerite and bultfonteinite from skarns of Tazheran alkaline massif. Geologiya i Geofizika: 2: 74-78.
Holtstam, Dan, Langhof, Jörgen, Holtstam, Dan, Langhof, Jörgen (1995) Metamorphic harkerite from Nordmarks Odalfält, Värmland, Sweden. GFF, 117 (3). 151-152 doi:10.1080/11035899509546211
Grew, Edward S.; Anovitz, Lawrence M. - Eds. (1996) Boron - Mineralogy, Petrology and Geochemistry. Reviews in Mineralogy Vol. 33. Mineralogical Society of America p.862
(2001) Harkerite. Handbook of Mineralogy. Mineralogical Society of America
Evans, R. James, Groat, Lee A., Cempírek, Jan, Škoda, Radek, Grew, Edward S., Bernard, Cyrielle (2018) The crystal chemistry of the sakhaite–harkerite solid solution. American Mineralogist, 103 (11) 1749-1760 doi:10.2138/am-2018-6563
Miyawaki, R., Hatert, F., Pasero, M., & Mills, S. (2021). Newsletter 60. Mineralogical Magazine, 85(3), 454-458.

Localities for HarkeriteHide

Showing 13 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.
China
 
  • Guangdong
    • Heyuan
      • Lianping Co.
Wang (1983) +1 other reference
Italy
 
  • Lazio
    • Metropolitan City of Rome Capital
Barbieri et al. (1973) +1 other reference
Juroszek et al. (Ti 5 Fe)
      • Bracciano
Cavarretta et al. (1987) +2 other references
Kazakhstan
 
  • Karaganda Region
    • Balkhash
      • Sayak Cu ore field
Pekov (1998)
Namibia
 
  • Otjozondjupa Region
    • Otavi Constituency
      • Kombat
Dunn (1991)
Russia
 
  • Sakha
    • Polar Yakutia
      • Dogdo River Basin
        • Tas-Khayakhtakh Range
Aleksandrov (1998)
Koneva et al. (1991)
Sweden
 
  • Värmland County
    • Filipstad
      • Nordmark Odal Field
Holtstam et al. (1995)
UK
 
  • Scotland
    • Highland
      • Eilean á Chèo
        • Isle of Skye
          • Broadford
            • Kilchrist
            • Torrin
Tilley (1951)
USA
 
  • California
    • Riverside County
      • Jurupa Valley
        • Crestmore
Grew et al. (1999) +1 other reference
  • New York
    • Essex County
      • Keene Township
        • Cascade Mountain
Grew et al. (1999) +1 other reference
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