For Dr. William Thomas Pecora II (1 February 1913, Belleville, New Jersey, USA - 19 July 1972, Washington, D.C., USA), Director of the United States Geological Survey (from 1965 to 1971) and student of nickel silicate deposits. The William T. Pecora Award was established in 1974 to honour Pecora, and is sponsored jointly by the Department of the Interior and the National Aeronautics and Space Administration (NASA). It is presented annually to individuals or groups that make outstanding contributions toward understanding the Earth by means of remote sensing.

Type Locality:

ⓘ Wolfe Creek meteorite crater, Carranya Station, Halls Creek Shire, Western Australia, Australia

Dimorph of:

Népouite

Kaolinite-Serpentine Group
Nickel analogue of chrysotile.

Unique IdentifiersHide

Mindat ID:

3139

Long-form identifier:

mindat:1:1:3139:0

Similar NamesHide

Picrite	A rock classification type
Picrite (of Brogniart)	A synonym of Dolomite
Yecoraite	A valid IMA mineral species	Fe₃³⁺Bi₅(Te⁶⁺O₄)₂(Te⁴⁺O₃)O₉ · 9H₂O

IMA Classification of PecoraiteHide

IMA status:

Approved

IMA Formula:

Ni₃Si₂O₅(OH)₄

First published:

1969

Type description reference:

Faust, G. T., Fahey, J. J., Mason, B., Dwornik, E. J. (1969) Pecoraite, Ni6Si4O10(OH)8, Nickel Analog of Clinochrysotile, Formed in the Wolf Creek Meteorite. Science, 165 (3888). 59-60 doi:10.1126/science.165.3888.59

Classification of PecoraiteHide

Strunz-mindat (2026):

9.ED.15

9 : SILICATES (Germanates)
E : Phyllosilicates
D : Phyllosilicates with kaolinite layers composed of tetrahedral and octahedral nets

Dana 8th ed.:

71.1.2d.4

71 : PHYLLOSILICATES Sheets of Six-Membered Rings
1 : Sheets of 6-membered rings with 1:1 layers

Hey's CIM Ref.:

14.26.2

14 : Silicates not Containing Aluminum
26 : Silicates of Ni

Mineral SymbolsHide

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.

Symbol	Source	Reference for Standard
Pco	IMA–CNMNC	Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
Pco	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 PecoraiteHide

Lustre:

Vitreous, Waxy, Earthy

Transparency:

Transparent, Translucent

Colour:

Green, blue-green yellow-green

Density:

3.084 g/cm³ (Measured) 3.47 g/cm³ (Calculated)

Comment:

Measured with absorbed water

Optical Data of PecoraiteHide

Type:

Biaxial (+/-)

RI values:

n_α = 1.565 - 1.603 n_β = 1.565 - 1.603 n_γ = 1.565 - 1.603

Max. Birefringence:

δ = 0.000
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.

Surface Relief:

Moderate

Dispersion:

r > v strong

Chemistry of PecoraiteHide

Mindat Formula:

Ni₃(Si₂O₅)(OH)₄

Element Weights:

Element	% weight
Ni	46.303 %
O	37.866 %
Si	14.771 %
H	1.060 %

Calculated from ideal end-member formula.

Elements listed:

H, Ni, O, Si - search for minerals with similar chemistry

Common Impurities:

Al,Fe,Mg,Ca,H₂O

Crystallography of PecoraiteHide

Crystal System:

Monoclinic

Cell Parameters:

a = 5.26 Å, b = 9.16 Å, c = 14.7 Å
β = 92°

Ratio:

a:b:c = 0.574 : 1 : 1.605

Unit Cell V:

707.84 Å³ (Calculated from Unit Cell)

Morphology:

Curved plates, spirals, and tubes, granular, massive.

Comment:

Point Group: n.d.; Space Group: n.d.

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
7.43 Å	(100)
3.66 Å	(75)
1.529 Å	(75)
4.50 Å	(62)
2.620 Å	(62)
2.447 Å	(50)

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Stage 5: Initiation of plate tectonics	<3.5-2.5
38 : Ophiolites
Stage 7: Great Oxidation Event	<2.4
47i : [Terrestrial weathering of meteorites]

Geological Setting:

Shears in ultramafic rocks, weathering product of millerite in geodes.

Type Occurrence of PecoraiteHide

Type Locality:

ⓘ Wolfe Creek meteorite crater, Carranya Station, Halls Creek Shire, Western Australia, Australia

General Appearance of Type Material:

Green grains, 0.1 to 5 mm in diameter, filling cracks a meteorite.

Place of Conservation of Type Material:

National Museum of Natural History, Washington, D.C., USA, 128111.

Geological Setting of Type Material:

Weathered meteorite

Associated Minerals at Type Locality:

Reference:

Synonyms of PecoraiteHide

IMA1969-005

Other Language Names for PecoraiteHide

Dutch:Pecoraiet

German:Pecorait

Simplified Chinese:镍纤蛇纹石

Spanish:Pecoraita

Traditional Chinese:鎳纖蛇紋石

Relationship of Pecoraite to other SpeciesHide

Member of:

Serpentine Subgroup > Kaolinite-Serpentine Group

Other Members of Serpentine Subgroup:

Amesite	Mg₂Al(AlSiO₅)(OH)₄	Tric. 1 : P1
Antigorite	Mg₃(Si₂O₅)(OH)₄	Mon. m : Bm
Berthierine	(Fe²⁺,Fe³⁺,Al)₃(Si,Al)₂O₅(OH)₄	Mon. m : Bm
Brindleyite	(Ni,Al)₃(Si,Al)₂O₅(OH)₄	Mon.
Caryopilite	Mn²⁺₃Si₂O₅(OH)₄	Mon.
Chrysotile	Mg₃(Si₂O₅)(OH)₄	Mon. m : Bb
Cronstedtite	Fe²⁺₂Fe³⁺((Si,Fe³⁺)₂O₅)(OH)₄	Trig. 3m : P31m
Fraipontite	(Zn,Al)₃((Si,Al)₂O₅)(OH)₄	Mon.
Guidottiite	Mn₂Fe³⁺(Fe³⁺SiO₅)(OH)₄	Hex. 6 : P6₃
Kellyite	Mn²⁺₂Al(AlSiO₅)(OH)₄	Hex. 6 : P6₃
Lizardite	Mg₃(Si₂O₅)(OH)₄	Trig. 3m : P31m
Népouite	Ni₃Si₂O₅(OH)₄	Orth.

Common AssociatesHide

Associations Based on Photo Data:

7 photos of Pecoraite associated with Nullaginite	Ni₂(CO₃)(OH)₂
6 photos of Pecoraite associated with Gaspéite	NiCO₃
4 photos of Pecoraite associated with Millerite	NiS
3 photos of Pecoraite associated with Cinnabar	HgS
2 photos of Pecoraite associated with Quartz	SiO₂
2 photos of Pecoraite associated with 'Garnierite'
2 photos of Pecoraite associated with Serpentine Subgroup	D₃[Si₂O₅](OH)₄
2 photos of Pecoraite associated with Talc	Mg₃Si₄O₁₀(OH)₂
1 photo of Pecoraite associated with Willemseite	Ni₃Si₄O₁₀(OH)₂
1 photo of Pecoraite associated with Aragonite	CaCO₃

Related Minerals - Strunz-mindat Grouping Hide

9.ED.	'Clinochrysotile'	Mg₃(Si₂O₅)(OH)₄	Mon. 2/m
9.ED.05	Dickite	Al₂(Si₂O₅)(OH)₄	Mon. m : Bb
9.ED.05	Nacrite	Al₂(Si₂O₅)(OH)₄	Mon. m : Bb
9.ED.05	Kaolinite	Al₂(Si₂O₅)(OH)₄	Tric. 1 : P1
9.ED.05	Odinite	(Fe,Mg,Al,Fe,Ti,Mn)_2.4((Si,Al)₂O₅)(OH)₄	Mon. m : Bm
9.ED.10	Halloysite	Al₂Si₂O₅(OH)₄ · n(H₂O)	Mon. m : Bb
9.ED.10	Hisingerite	Fe³⁺₂(Si₂O₅)(OH)₄ · 2H₂O	Mon.
9.ED.10	'Hydrohalloysite'	Al₂Si₂O₅(OH)₄ · 2H₂O	Mon. m
9.ED.15	Antigorite	Mg₃(Si₂O₅)(OH)₄	Mon. m : Bm
9.ED.15	Brindleyite	(Ni,Al)₃(Si,Al)₂O₅(OH)₄	Mon.
9.ED.15	Fraipontite	(Zn,Al)₃((Si,Al)₂O₅)(OH)₄	Mon.
9.ED.15	Népouite	Ni₃Si₂O₅(OH)₄	Orth.
9.ED.15	Guidottiite	Mn₂Fe³⁺(Fe³⁺SiO₅)(OH)₄	Hex. 6 : P6₃
9.ED.15	Lizardite	Mg₃(Si₂O₅)(OH)₄	Trig. 3m : P31m
9.ED.15	Berthierine	(Fe²⁺,Fe³⁺,Al)₃(Si,Al)₂O₅(OH)₄	Mon. m : Bm
9.ED.15	Kellyite	Mn²⁺₂Al(AlSiO₅)(OH)₄	Hex. 6 : P6₃
9.ED.15	Cronstedtite	Fe²⁺₂Fe³⁺((Si,Fe³⁺)₂O₅)(OH)₄	Trig. 3m : P31m
9.ED.15	Caryopilite	Mn²⁺₃Si₂O₅(OH)₄	Mon.
9.ED.15 va	'Chromoamesite'	Mg₂(Al,Cr)(AlSiO₅)(OH)₄
9.ED.15	Amesite	Mg₂Al(AlSiO₅)(OH)₄	Tric. 1 : P1
9.ED.15	Greenalite	(Fe²⁺,Fe³⁺)_2-3Si₂O₅(OH)₄	Mon.
9.ED.15	Manandonite	Li₂Al₄(Si₂AlB)O₁₀(OH)₈	Orth. 222 : C222₁
9.ED.20	Chrysocolla	Cu_2-xAl_x(H_2-xSi₂O₅)(OH)₄ · nH₂O, x < 1	Orth.
9.ED.20	Neotocite	(Mn,Fe)SiO₃ · H₂O (?)	Amor.
9.ED.20	Allophane	(Al₂O₃)(SiO₂)_1.3-2 · 2.5-3H₂O	Amor.
9.ED.20	Imogolite	Al₂SiO₃(OH)₄
9.ED.25	Bismutoferrite	Fe³⁺₂Bi(SiO₄)₂(OH)	Mon. m : Bm
9.ED.25	Chapmanite	Fe³⁺₂Sb³⁺(Si₂O₅)O₃(OH)	Mon. m : Bm
9.ED.30	'Pianlinite'	Al₂Si₂O₆(OH)₂	Orth.

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 PecoraiteHide

mindat.org URL:

https://www.mindat.org/min-3139.html
Please feel free to link to this page.

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Look for Pecoraite in the Rock H. Currier Digital Library

External Links:

Look for Pecoraite on Webmineral

Look for Pecoraite on Wikipedia

Look for Pecoraite on Mineralien Atlas

Raman and XRD data at RRUFF project

References and PDF downloads at RRUFF project

American Mineralogist Crystal Structure Database

Handbook of Mineralogy page PDF

Mineral Dealers:

Buy from D. Joyce minerals

Buy from McDougall Minerals

The Arkenstone - Fine Minerals

References for PecoraiteHide

Reference List:

Fleischer, Michael (1969) New Mineral Names. American Mineralogist, 54 (11-12) 1737-1742 p.1740

Faust, George T., Fahey, J.J., Mason, B.H., Dwornik, E.J. (1973) The disintegration of the Wolf Creek meteorite and the formation of pecoraite, the nickel analog of clinochrysotile. Professional Paper 384c. US Geological Survey doi:10.3133/pp384c

Milton, C., E.J. Dwornik, R.B. Finkelman (1983) Pecoraite, the nickel analogue of chrysotile, Ni3Si2O5(OH)4 from Missouri. Neues Jahrbuch für Mineralogie, Monatshefte 11: 513-523.

(2001) Pecoraite. Handbook of Mineralogy. Mineralogical Society of America

Frost, Ray L., Jagannadha Reddy, B., Dickfos, Marilla J. (2008) Raman spectroscopy of the nickel silicate mineral pecoraite—an analogue of chrysotile (asbestos). Journal of Raman Spectroscopy, 39 (7). 909-913 doi:10.1002/jrs.1933

Localities for PecoraiteHide

Showing 49 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the 👁 Image
symbol to view information about a locality. The 👁 Image
symbol next to localities in the list can be used to jump to that position on the map.

Hide all sections | Show all sections

Locality ListHide

👁 Image
- This locality has map coordinates listed. 👁 Image
- This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. 👁 Image
- Good crystals or important locality for species. 👁 Image
- 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.

Australia
Tasmania Waratah-Wynyard municipality Heazlewood district ⓘ Lord Brassey Mine	Bottrill et al. (2002)
Western Australia Coolgardie Shire Kambalda Kambalda Nickel mines Juan complex ⓘ Otter Shoot Nickel Mine	Nickel et al. (1981)
Widgiemooltha ⓘ 132 North Ni Mine	Nickel et al. (1993) +1 other reference
East Pilbara Shire Nullagine ⓘ Otway Ni deposit	Nickel +2 other references
Halls Creek Shire Carranya Station ⓘ Wolfe Creek meteorite crater (TL)	Faust et al. (1969) +2 other references
Menzies Shire Menangina Station ⓘ Carr Boyd Rocks Ni mine	Nickel et al. (1981) +1 other reference
Canada
Québec Estrie Le Val-Saint-François RCM St-Denis-de-Brompton ⓘ Orford Nickel mine	Gault et al. (1994)
Dominican Republic
Monseñor Nouel Province Bonao Falcondo Mines ⓘ Loma Peguera deposit	M.E. Ciriotti (Steffen Moeckel analysis)
France
New Caledonia Northern Province Houaïlou ⓘ Poro Mine	Berger et al. (2011) +1 other reference
Pouembout ⓘ Népoui Mine	Berger et al. (2011) +1 other reference
Provence-Alpes-Côte d'Azur Alpes-Maritimes Nice Arrondissement Daluis ⓘ Roua Mines (Clue de Roua)	Mandarino (2001)
Germany
Saxony Vogtlandkreis Limbach ⓘ Reimersgrün Quarry	Tröger (2012)
Plauen Röttis ⓘ Hans Georg Mine	Gerstenberg (n.d.)
Pöhl ⓘ Rentzschmühle Quarry	M Adelt collection
Greece
Attica East Attica Lavreotiki Km 3 Km 3 mines ⓘ Km 3 open pit	Möckel (2000)
Italy
Liguria Genoa Ceranesi Livellato Case Lagoscuro ⓘ Lagoscuro mine	Biagioni et al. (2020)
Lombardy Sondrio Province Lanzada Campo Moro Valley ⓘ Alpe Gera	Bedognè et al. (1993)
Franscia ⓘ Dossi di Franscia ?	Bedognè et al. (1993)
ⓘ Vallone del Cengiaccio (Cengiaccio; Cengiàsc; Cengiasco)	Bedognè et al. (1993) +1 other reference
ⓘ Malenco Valley	Bedogné et al. (1994)
Torre di Santa Maria ⓘ Val Sora Quarry	Guicciardi (1980)
Piedmont Verbano-Cusio-Ossola Province Villette ⓘ Pian dei Sali serpentinite (Monte Netto - Cresta della Colmine northwest slope)	Boscardin et al. (2013)
Sardinia South Sardinia Province Nuxis Monte Tamara mining area ⓘ San Pietro Mine	Lecca et al. (2022)
Tuscany Livorno Province Livorno ⓘ Botro del Diavolo	Marco Bonifazi collection
Lucca Province Stazzema Pontestazzemese ⓘ Buca della Vena Mine	Orlandi (2011)
Morocco
Drâa-Tafilalet Region Zagora Province Agdz Cercle Tansifte Caïdat ⓘ Aït Ahmane	Färber (n.d.)
Russia
Chelyabinsk Oblast Verkhny Ufaley Ufaley District (Ufalei District) ⓘ Novocheremshanskiy Nickel Mine	Talovina et al. (2008) +2 other references
ⓘ Sinar Nickel Mine	Talovina et al. (2008)
ⓘ Ufalei Ni deposit	Talovina et al. (2003)
Sverdlovsk Oblast Rezhevsky District Lipovsk pegmatite field ⓘ Lipovka Mine (Lipovskoe Mine; Lipovskaya Mine; Lipovaya Mine)	Pavel.M. Kartashov (n.d.)
Serovsky District Serov Kola massif ⓘ Elov Mine	Talovina et al. (2008)
ⓘ Ural Economic Region	...
South Africa
Mpumalanga Ehlanzeni District Municipality Mbombela Local Municipality Kaapschehoop ⓘ New Amianthus Mine	Cairncross et al. (1995)
South Korea
Gyeonggi Province Gwacheon City ⓘ Buksite	Song et al. (1995) +1 other reference
ⓘ Namsite	Song et al. (1995)
Turkey
Manisa Province Turgutlu District ⓘ Çaldağ Mine	Helvaci et al. (2013)
USA
Arizona Cochise County Turquoise Mining District (Courtland-Gleeson Mining District) ⓘ Barrett Camp ghost town	Anthony et al. (1995)
California San Benito County Goat Mountain ⓘ Clear Creek claim	Dunning et al. (2005)
Idria (New Idria) ⓘ New Idria Mine (New Idria group; New Hope vein)
Sonoma County West Mayacmas Mining District Cloverdale North Fork Little Sulphur Creek ⓘ Culver-Baer Mine	Tim Greenland (2011)
Maryland Montgomery County Rockville ⓘ Hunting Hill Quarry	Parker (2014)
Michigan Marquette County Ishpeming Township Ishpeming Greenstone belt (Marquette Greenstone belt) ⓘ Ropes Gold Mine	Travis Olds collection
Marquette ⓘ Presque Isle	George W. Robinson and S.M. Carlson (2009)
Missouri Jefferson County ⓘ Antire Road Quarry	Sherwood et al. (1998)
ⓘ St. Louis County	www.gswweb.org/minutes/GSW1980.htm
ⓘ St. Louis and Spergen limestones	Sherwood et al. (1998)
New York Jefferson County Antwerp ⓘ Sterling Mine	Robinson et al. (2007)
Oregon Douglas County Riddle Mining District Riddle ⓘ Riddle Mine	...
Vermont Orleans & Lamoille Cos. Lowell & Eden ⓘ Belvidere Mountain Quarries	Rocks & Min. Vol. 71 (1996)

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