Mindat Logo
Home Page Log In Message Board The Mindat Directory
Register Search Pages Chat Now! (2 online) Mindat Auctions

Pectolite

Big Photo

Poudrette quarry (Demix quarry; Uni-Mix quarry; Desourdy quarry), Mont Saint-Hilaire, Rouville Co., Québec, Canada

Show Pectolite Photos (176)
Formula:
NaCa
 
2
[HSi
 
3
O
 
9
]
System:TriclinicColour:Colourless, white, pale ...
Hardness:4½ - 5
Name:From the Greek for compact, in allusion to its resistance to pulverization.


Wollastonite Group. Pectolite-Schizolite-Sérandite Series. The calcium analogue of Sérandite.

Classification of Pectolite

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:8/F.18-60
Nickel-Strunz 10th (pending) edition ID:9.DG.05

9 : SILICATES (Germanates)
D : Inosilicates
G : Inosilicates with 3-periodic single and multiple chains
Dana 8th edition ID:65.2.1.4a

65 : INOSILICATES Single-Width,Unbranched Chains,(W=1)
2 : Single-Width Unbranched Chains, W=1 with chains P=3
Hey's CIM Ref.:14.6.2

14 : Silicates not Containing Aluminum
6 : Silicates of Ca with alkali or Mg or both
mindat.org URL:http://www.mindat.org/min-3141.html
Please feel free to link to this page.

Type Occurrence of Pectolite

Co-type Localities:Monzoni Mts, Fassa Valley, Trento Province, Trentino-Alto Adige, Italy
Sano, Mori, Mt. Baldo, Trento Province, Trentino-Alto Adige, Italy
Year of Discovery:1828

Occurrences of Pectolite

Geological Setting:Primary mineral in nepheline syenites. Hydrothermal mineral in cavities in basalts and diabases. In serpentinites and peridotites.

Physical Properties of Pectolite

Lustre:Sub-Vitreous, Silky
Diaphaneity (Transparency):Transparent, Translucent
Colour:Colourless, white, pale pink, greenish, pale blue
Streak:White
Hardness (Mohs):4½ - 5
Tenacity:Brittle
Cleavage:Perfect
on {100} and {001}
Fracture:Irregular/Uneven
Comment:Tough when compact.
Density (measured):2.84 - 2.9 g/cm3
Density (calculated):2.87 g/cm3

Crystallography of Pectolite

Crystal System:Triclinic
Class (H-M):1 - Pinacoidal
Space Group:P1
Cell Parameters:a = 7.99Å, b = 7.03Å, c = 7.03Å
α = 90.51°, β = 95.21°, γ = 102.53°
Ratio:a:b:c = 1.137 : 1 : 1
Unit Cell Volume:V 383.71 ų (Calculated from Unit Cell)
Z:2
Morphology:Crystals tabular, acicular. Radiating fibrous, spheroidal, columnar, fine-grained, massive.
Twinning:Common with twin axis [010], composition plane {100}
X-Ray Powder Diffraction:
Image Loading

Radiation - Copper Kα
Data Set:
Horizontal Axis: ° to ° Vertical Axis: % Source Data: Filtered Data: Peaks:
Data courtesy of RRUFF project at University of Arizona, used with permission.

Optical Data of Pectolite

Type:Biaxial (+)
RI values: nα = 1.594 - 1.610 nβ = 1.603 - 1.614 nγ = 1.631 - 1.642
2V:Measured: 50° to 63°, Calculated: 42° to 60°
Maximum Birefringence:δ = 0.037

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Moderate
Dispersion:r > v weak to very strong

Chemical Properties of Pectolite

Formula:
NaCa
 
2
[HSi
 
3
O
 
9
]
Essential elements:Ca, H, Na, O, Si
All elements listed in formula:Ca, H, Na, O, Si
Common Impurities:K,Fe,Mg,Al,H2O

Relationship of Pectolite to other Species

Series:Forms a series with Sérandite (see here)
Related Minerals - Nickel-Strunz Grouping):

- +
9.DG.05Bustamite
(Mn
2+
 
,Ca)[SiO
 
3
]
9.DG.05Ferrobustamite
Ca(Fe
2+
 
,Ca,Mn
2+
 
)[Si
 
2
O
 
6
]
9.DG.05Sérandite
Na(Mn
2+
 
,Ca)
 
2
[HSi
 
3
O
 
9
]
9.DG.05Wollastonite
Ca[SiO
 
3
]
9.DG.05Wollastonite-1A
CaSiO
 
3
9.DG.07Cascandite
Ca(Sc,Fe
3+
 
)[HSi
 
3
O
 
9
]
9.DG.08Plombièrite
Ca
 
5
Si
 
6
O
 
16
(OH)
 
2
·7H
 
2
O
9.DG.10Clinotobermorite
Ca
 
5
[Si
 
3
O
 
8
(OH)
 
2
]2.4H
 
2
O - Ca
 
5
[Si
 
6
O17]·5H
 
2
O
9.DG.10Riversideite
Ca
 
5
Si
 
6
O
 
16
(OH)
 
2
·2H
 
2
O
9.DG.10Tobermorite
Ca
 
5
Si
 
6
(O,OH)
 
18
·5H
 
2
O
9.DG.15Foshagite
Ca
 
4
[(OH)
 
2
|Si
 
3
O
 
9
]
9.DG.20Jennite
Ca
 
9
H
 
2
Si
 
6
O
 
18
(OH)
 
8
·6H
 
2
O
9.DG.25Paraumbite
K
 
3
Zr
 
2
H(Si
 
3
O
 
9
)
 
2
·nH
 
2
O
9.DG.25Umbite
K
 
2
(Zr,Ti)Si
 
3
O
 
9
·H
 
2
O
9.DG.30Sørensenite
Na
 
4
SnBe
 
2
Si
 
6
O
 
16
(OH)
 
4
9.DG.35Xonotlite
Ca
 
6
Si
 
6
O
 
17
(OH)
 
2
9.DG.40Hillebrandite
Ca
 
2
[(OH)
 
2
|SiO
 
3
]
9.DG.45Zorite
Na
 
2
Ti(Si,Al)
 
3
O
 
9
·nH
 
2
O
9.DG.45Chivruaiite
Ca
 
3
Ti
 
5
[(Si
 
6
O
 
17
)
 
2
|O(OH)
 
4
]·14H
 
2
O
9.DG.50Haineaultite
(Na,Ca)
 
5
Ca(Ti,Nb)
 
5
[(OH,F)
 
4
|Si
 
6
O
 
17
]
 
2
 · 5H
 
2
O
9.DG.55Epididymite
Na
 
2
Be
 
2
Si
 
6
O
 
15
·H
 
2
O
9.DG.60Eudidymite
Na
 
2
Be
 
2
Si
 
6
O
 
15
·H
 
2
O
9.DG.65Elpidite
Na
 
2
ZrSi
 
6
O
 
15
·3H
 
2
O
9.DG.70Fenaksite
(K,Na)
 
4
(Fe,Mn)
 
2
(Si
 
4
O
 
10
)
 
2
(OH,F)
9.DG.70Litidionite
CuNaKSi
 
4
O
 
10
9.DG.70Manaksite
KNaMnSi
 
4
O
 
10
9.DG.75Tinaksite
K
 
2
Na(Ca,Mn
2+
 
)
 
2
Ti[O|Si
 
7
O
 
18
(OH)]
9.DG.75Tokkoite
K
 
2
Ca
 
4
Si
 
7
O
 
17
(O,OH,F)
 
4
9.DG.75Senkevichite
CsKNaCa
 
2
Ti[O|Si
 
7
O
 
18
(OH)]
9.DG.80Canasite
K
 
2
Na
 
4
Ca
 
5
(Si
 
12
O
 
30
(OH,F)
 
4
9.DG.80Fluorcanasite
K
 
3
Na
 
3
Ca
 
5
Si
 
12
O
 
30
F
 
4
·H
 
2
O
9.DG.85Miserite
K(Ca,Ce)
 
4
Si
 
5
O
 
13
(OH)
 
3
9.DG.90Frankamenite
K
 
3
Na
 
3
Ca
 
5
(Si
 
12
O
 
30
)[F,(OH)]
 
4
·H
 
2
O
9.DG.92Charoite
(K,Na)
 
5
(Ca,Ba,Sr)
 
8
(Si
 
6
O
 
15
)
 
2
(Si
 
6
O
 
16
)(OH,F)·H
 
2
O
9.DG.95Yuksporite
(K,Ba)NaCa
 
2
(Si,Ti)
 
4
O
 
11
(F,OH)·H
 
2
O
9.DG.97Eveslogite
(Na,K,Ca,Sr,Ba)
 
48
 [(Ti,Nb,Mn,Fe
2+
 
)
 
12
Si
 
48
O
 
144
(OH)
 
12
](F,OH,Cl)
 
14
Related Minerals - Hey's Index Grouping:

- +
14.6.1Combeite
Na
 
2
Ca
 
2
Si
 
3
O
 
9
14.6.3Pectolite-M2abc
NaCa
 
2
[HSi
 
3
O
 
9
]
14.6.4Denisovite
Ca
 
2
(K,Na)Si
 
3
O
 
8
(F,OH)
 
2
14.6.5Tokkoite
K
 
2
Ca
 
4
Si
 
7
O
 
17
(O,OH,F)
 
4
14.6.6Mountainite
(Ca,Na
 
2
,K
 
2
)
 
2
[Si
 
4
O
 
10
] · 3H
 
2
O
14.6.7Rhodesite
KHCa
 
2
Si
 
8
O
 
19
·5H
 
2
O
14.6.8Miserite
K(Ca,Ce)
 
4
Si
 
5
O
 
13
(OH)
 
3
14.6.9Åkermanite
Ca
 
2
Mg[Si
 
2
O
 
7
]
14.6.10Monticellite
CaMg[SiO
 
4
]
14.6.11Merwinite
Ca
 
3
Mg[SiO
 
4
]
 
2
14.6.12Diopside
CaMg[Si
 
2
O
 
6
]
14.6.13Tremolite
☐[Ca
 
2
][Mg
 
5
][(OH)
 
2
|Si
 
8
O
 
22
]

Other Names for Pectolite

Synonyms:
Alaska JadeGonsogolitePecktolitePektolithStellite
Other Languages:
German:Gonsogolit
Pecktolit
Pectolit
Russian:Пектолит
Spanish:Gonsogolita
Pecktolita
Pectolita
Varieties:
LarimarManganoan Pectolite

Polytypes for Pectolite

Polytypes:
Pectolite-M2abc

Other Information

Other Information:May be triboluminescent.
Health Warning:The white needles of pectolite are sharp and stiff and easily penetrate the skin. Once embedded they are invisible and brittle and difficult to remove, often very painful. Handle with caution at all times. Do not rub your hands after handling. Rinse hands in a strong stream of water before handling anything else, especially food.

References for Pectolite

Reference List:American Mineralogist (1978): 63: 427.

Zeitschrift für Kristallographie: 108: 248-262.

Zeitschrift für Kristallographie: 125: 298-316.

Hammer, V.M.F., Libowitzky, E., and Rossman, G.R. (1998) Single-crystal IR spectroscopy of very strong hydrogen bonds in pectolite, NCa2[Si3O4(OH)], and serandite, NaMn2[Si3O4(OH)]. American Mineralogist: 83: 569-576.

Internet Links for Pectolite

Search Engines:
  • Look for Pectolite on Google
  • Look for Pectolite images on Google
    • External Links:
  • Look for Pectolite on Webmineral
  • Look for Pectolite on Athena Mineralogy
  • Look for Pectolite on Wikipedia
  • Look for Pectolite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Search for Pectolite in the Natural History Museum (London) online catalogue
  • Pectolite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • High-end worldwide specimens & outstanding customer service
  • The Arkenstone - Fine Minerals
  • Fine Minerals from Dan Weinrich Minerals
  • Top quality minerals from Kristalle of California
  • Fabre Minerals - search for Pectolite specimens
  • Search for Pectolite on minvision.com
  • Find Pectolite on www.crystalclassics.co.uk
  • rare and unusual minerals mainly crystallized
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
  • Rare and Unusual minerals at Mineralogical Research Company
  • Wilensky Fine Minerals
  • Lapis Mineral Magazin
    • Jobs:
  • Mining & Geology Jobs

    • Page Sponsor

    Sponsorship:This page is currently not sponsored. Click here to sponsor this page.

    Localities for Pectolite

    Show Locality List (252 Items)
    The 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.
    These maps work faster with Firefox!
    Mineral and/or Locality
    Google
     
    www.mindat.org Web
    Copyright © Jolyon Ralph and Ida Chau 1993-2009. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them.Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. If you would like to add information to improve the quality of our database, then click here to register.