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About GrayiteHide

(Th,Pb,Ca)(PO4) · H2O
Dark reddish brown, rarely tannish yellow
Resinous, Waxy, Greasy
Specific Gravity:
6.41 (Calculated)
Crystal System:
Named in honor of Anton Gray, chief geologist, Kennecott Copper Corporation and advisor to the United Kingdom Atomic Energy Authority.
Isostructural with:
Originally powdery or cryptocrystalline. Rarely in subhedral resinous crystals.

Compare 'UM1979-08-PO:CCaFeHREESiTh'; 'UM1980-04-PO:CaHREETh', 'UM1979-07-PO:CaFeHREESiTh'.

Classification of GrayiteHide

Approved, 'Grandfathered' (first described prior to 1959)

C : Phosphates without additional anions, with H2O
J : With only large cations

4 : (AB)5(XO4)2·xH2O

19 : Phosphates
10 : Phosphates of Pb, Th, V and Bi

Physical Properties of GrayiteHide

Resinous, Waxy, Greasy
Dark reddish brown, rarely tannish yellow
6.41 g/cm3 (Calculated)

Optical Data of GrayiteHide

RI values:
nα = 1.660 nβ = 1.690
Max Birefringence:
δ = 1.660
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
Surface Relief:

Chemical Properties of GrayiteHide

(Th,Pb,Ca)(PO4) · H2O

Crystallography of GrayiteHide

Crystal System:
Class (H-M):
6 2 2 - Trapezohedral
Space Group:
P62 2 2
Cell Parameters:
a = 6.957 Å, c = 6.396 Å
a:c = 1 : 0.919
Unit Cell V:
268.09 ų (Calculated from Unit Cell)

X-Ray Powder DiffractionHide

Powder Diffraction Data:
6.05 Å(20)
4.35 Å(50)
3.46 Å(10)
3.03 Å(100)
2.82 Å(80)
2.36 Å(10)
2.15 Å(80)
1.856 Å(50)

Type Occurrence of GrayiteHide

Other Language Names for GrayiteHide


Common AssociatesHide

Associated Minerals Based on Photo Data:
1 photo of Grayite associated with Allanite{A12+REE3+}{M3+2M32+}(Si2O7)(SiO4)O(OH)
1 photo of Grayite associated with Thorogummite(Th,U)(SiO4)1-x(OH)4x
1 photo of Grayite associated with Xenotime-(Y)Y(PO4)

Related Minerals - Nickel-Strunz GroupingHide

8.CJ.CaesiumpharmacosideriteCsFe4[(AsO4)3(OH)4]·4H2OIso. 4 3m : P4 3m
8.CJ.JeankempiteCa5(AsO4)2(HAsO4)2 · 7H2OTric. 1 : P1
8.CJ.05StercoriteNa(NH4)HPO4 · 4H2OTric.
8.CJ.10Mundrabillaite(NH4)2Ca(HPO4)2 · H2OMon. m : Pm
8.CJ.10Swaknoite(NH4)2Ca(HPO4)2 · H2OOrth.
8.CJ.15NabaphiteNaBaPO4 · 9H2OIso.
8.CJ.15NastrophiteNa(Sr,Ba)PO4 · 9H2O
8.CJ.20HaidingeriteCaHAsO4 · H2OOrth. mmm (2/m 2/m 2/m) : Pbcn
8.CJ.25VladimiriteCa4(AsO4)2(AsO3OH) · 4H2OMon. 2/m : P21/b
8.CJ.30FerrarisiteCa5(AsO4)2(HAsO4)2 · 9H2OTric. 1 : P1
8.CJ.35Machatschkiite(Ca,Na)6(AsO4)(HAsO4)3(PO4,SO4) · 15H2OHex.
8.CJ.40PhaunouxiteCa3(AsO4)2 · 11H2OTric.
8.CJ.40RauenthaliteCa3(AsO4)2 · 10H2OTric. 1 : P1
8.CJ.45Brockite(Ca,Th,Ce)PO4 · H2OHex. 6 2 2 : P62 2 2
8.CJ.45Rhabdophane-(Ce)Ce(PO4) · H2OHex. 6 2 2 : P62 2 2
8.CJ.45Rhabdophane-(La)La(PO4) · H2OHex. 6 2 2 : P62 2 2
8.CJ.45Rhabdophane-(Nd)Nd(PO4) · H2OHex. 6 2 2 : P62 2 2
8.CJ.45Tristramite(Ca,U,Fe)(PO4,SO4) · 2H2OHex.
8.CJ.45Smirnovskite(Th,Ca)PO4 · nH2OHex. 6 2 2 : P62 2 2
8.CJ.50ArdealiteCa2(HPO4)(SO4) · 4H2OMon. m : Bb
8.CJ.50BrushiteCa(HPO4) · 2H2OMon. m : Bb
8.CJ.50Churchite-(Y)Y(PO4) · 2H2OMon. 2/m : B2/b
8.CJ.50PharmacoliteCa(HAsO4) · 2H2OMon. m
8.CJ.50Churchite-(Nd)Nd(PO4) · 2H2OMon.
8.CJ.55McneariteNaCa5(AsO4)(HAsO4)4 · 4H2OTric.
8.CJ.60DorfmaniteNa2HPO4 · 2H2OOrth.
8.CJ.65SincositeCa(VO)2(PO4)2 · 5H2OTet. 4/mmm (4/m 2/m 2/m) : P42/nnm
8.CJ.65BariosincositeBa(VO)2(PO4)2 · 4H2OTet.
8.CJ.70CatalanoiteNa2(HPO4) · 8H2OOrth. mmm (2/m 2/m 2/m) : Ibca
8.CJ.75GuériniteCa5(AsO4)2(HAsO4)2 · 9H2OMon. 2/m : P21/b
8.CJ.85NingyoiteCaU(PO4)2 · 1-2H2OOrth.

Related Minerals - Dana Grouping (8th Ed.)Hide · H2OHex. 6 2 2 : P62 2 2 · H2OHex. 6 2 2 : P62 2 2,Th,Ce)PO4 · H2OHex. 6 2 2 : P62 2 2,U,Fe)(PO4,SO4) · 2H2OHex.

Related Minerals - Hey's Chemical Index of Minerals GroupingHide

19.10.2PlumbogummitePbAl3(PO4)(PO3OH)(OH)6Trig. 3m (3 2/m) : R3m
19.10.3KamitugaitePbAl[(UO2)5(PO4)2.38(AsO4)0.62O2(OH)2] · 11.5H2OTric. 1 : P1
19.10.5DrugmanitePb2(Fe3+,Al)(PO4)(PO3OH)(OH)2Mon. 2/m : P21/b
19.10.9Brockite(Ca,Th,Ce)PO4 · H2OHex. 6 2 2 : P62 2 2
19.10.10SincositeCa(VO)2(PO4)2 · 5H2OTet. 4/mmm (4/m 2/m 2/m) : P42/nnm
19.10.12Paulkellerite(BiO)2Fe3+(PO4)(OH)2Mon. 2/m : B2/b

Fluorescence of GrayiteHide

Specimens from Havey #2 Quarry, Topsham, Maine fluoresce yellow in SW UV.

Other InformationHide

Thermal Behaviour:
Grayite may give a monazite-like powder pattern after heating to 850 degrees 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.

References for GrayiteHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Bowie, 1957, Summary of Progress, Geological Survey of Great Britain for 1956, p. 67; Chronique mines outre-mer et recherche minere, v. 279 (1959); Dooley and Hathaway, 1961, USGS Professioal Paper 424-C; not American Mineralogist: 47: 419-420, contains no new data on the species.

Internet Links for GrayiteHide

Localities for GrayiteHide

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.

Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for 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 (eg from pseudomorphs.)

All localities listed without proper references should be considered as questionable.
  • Sofia City Province
    • Ihtimanska Sredna Gora (Ikhtiman Sredna Gora)
Zidarov, N., & Petrov, O. (2011) Grayite from Sredna Gora Pegmatites - First Find in Bulgaria. Comptes Rendus De L Academie Bulgare Des Sciences, 64(12), 1719-1726.
  • Saxony
    • Sächsische Schweiz-Osterzgebirge
      • Dippoldiswalde
Witzke, T. (2011): Neues von Sadisdorf, Erzgebirge: Gananit, Cheralith, Grayit und Brockit. Mineralien-Welt 22 (4), 47-50.
  • Fukushima Prefecture
    • Koriyama City
Terada et al (1994) Chigaku Kenkyu, 43, 181-185.
  • Erongo Region
    • Karibib
Joan Rosell. RosellMinerals.com
  • Lower Silesian Voivodeship
    • Zgorzelec Co.
Kucha H., Wieczorek A. 1980: Ca1-xTh1-xRE2x[PO4]2 . 2H2O, a new mineral from Lower Silesia, Poland. Mineralogia Polonica, vol. 11, No 1, 123-136; Mochnacka, K., Oberc-Dziedzic, T., Mayer, W., & Pieczka, A. (2015). Ore mineralization related to geological evolution of the Karkonosze–Izera Massif (the Sudetes, Poland)—Towards a model. Ore Geology Reviews, 64, 215-238.
  • Western Region
    • Mbarara District
      • Ankole pegmatite field
Gallagher, M.J. (1967): Phosphates and other minerals in pegmatites of Rhodesia and Uganda. Mineralogical Magazine. 36, 50-59
  • Colorado
    • Gunnison Co.
      • Quartz Creek Pegmatite Mining District
Minerals of Colorado (1997) Eckel, E. B.
      • White Earth Mining District (Powderhorn Mining District)
"Minerals of Colorado, updated & revised", p. 17, by Eckel, Edwin B., 1997
    • Park Co.
      • Guffey Mining District
Rudy Bolona
  • Connecticut
    • Hartford Co.
      • Glastonbury
        • South Glastonbury
Specimen in collection of Andrew Kruegel
    • Middlesex Co.
      • East Hampton (Chatham)
Fred Davis - home.att.net/~fedavis/Main/Page_109.html
  • Maine
    • Sagadahoc Co.
      • Topsham
King, V. and Foord, E., 1994, Mineralogy of Maine.
  • Michigan
    • Dickinson Co.
      • Randville
Buchholz, T.W., A.U. Falster & W.B. Simmons (2014), Accessory Mineralogy of an Evolved Dickinson County, Michigan, Pegmatite, a presentation before the 41st. Rochester Mineralogical Symposium, April 25, 2014.
    • Marquette Co.
      • Republic
Buchholz, T.W., Falster, A.U. and Simmons, W.B. (2013) Accessory mineralogy of the Black River pegmatite and Humboldt granite, Marquette County, Michigan. The 40th Rochester Mineralogical Symposium, Contributed Papers in Specimen Mineralogy, 9-10.
  • Nevada
    • Mineral Co.
      • Fitting Mining District
        • Gillis Range
Mineralogical Record: 30: 277-292.
  • Wisconsin
    • Dodge Co.
Buchholz, T.W.. et al (2002) 29th Rochester Mineralogical Symposium, Abstracts of contributed papers, 6.; Buchholz, Thomas W., Falster, Alexander U. and Simmons, Wm. B. (2016) Pegmatite Mineralogy of the Waterloo Quarry, Southern Wisconsin, USA. in Second Eugene E. Foord Pegmatite Symposium July 15-19, 2016 Colorado School of Mines campus, Golden, Colorado
    • Marathon Co.
      • Wausau Intrusive Complex
        • Nine Mile Pluton
Cordura, W http://www.uwex.edu/wgnhs/Mineral%20Index/Minerals/grayite.htm
Zimbabwe (TL)
  • Mashonaland East
    • Mutoko District (Mtoko District)
      • Mutoko parish (Mtoko)
American Mineralogist 47 (1962), 419.; Ackermann, K.J., Branscombe, K.C., Hawkes, J.R., Tidy, A.J.L. (1968) The geology of some beryl pegmatites in Southern Rhodesia. Verhandelinge van die Geologiese Vereniging van Suid Afrika (Transactions of the Geological Society of South Africa), 69(1), 1-38.
    • Wedza District
Bowie, 1957, Summary of Progress, Geological Survey of Great Britain for 1956
Mineral and/or Locality  
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