Cowlesite
A valid IMA mineral species
This page kindly sponsored by Douglas Merson
About Cowlesite
John Cowles collecting at Altoona, Wa in 1971
Unnamed Basalt quarry, Altoona, Wahkiakum County, Washington, USA
Unnamed Basalt quarry, Altoona, Wahkiakum County, Washington, USA
Formula:
CaAl2Si3O10 · 6H2O
Colour:
Colourless, white
Lustre:
Vitreous, Greasy
Hardness:
5 - 5½
Specific Gravity:
2.14
Crystal System:
Orthorhombic
Member of:
Name:
Named in 1975 in honor of John Cowles (9 January 1907, Nebraska, USA - 13 December 1985, Oregon, USA) of Rainier, Oregon, amateur mineralogist and enthusiastic zeolite collector, whose deep interest in zeolite mineralogy led him to discover new localities for ferrierite, dachiardite, erionite and the co-type locality for cavansite. Pronounced kĆl-sait.
Co-Type Localities:
â Monte Lake, Kamloops Mining Division, British Columbia, Canada
â Unnamed wash, adjacent to State Route 177, Superior area, Pinal County, Arizona, USA
â North Table Mountain, Golden, Golden Mining District, Jefferson County, Colorado, USA
â Neer Road, Goble, Columbia County, Oregon, USA
â Beech Creek Quarry, Mount Vernon, Grant County, Oregon, USA
â Unnamed wash, adjacent to State Route 177, Superior area, Pinal County, Arizona, USA
â North Table Mountain, Golden, Golden Mining District, Jefferson County, Colorado, USA
â Neer Road, Goble, Columbia County, Oregon, USA
â Beech Creek Quarry, Mount Vernon, Grant County, Oregon, USA
Zeolite Group.
Unlike other zeolites, cowlesite has a very limited compositional range (Vezzalini et al., 1992).
The crystal structure resisted its determination by X-ray diffraction methods for a very long time, and only in 2020 the structure could be finally solved by electron diffraction under cryo conditions (Mugnaioli et al., 2020).
Cowlesite is the only two-dimensional (2D) zeolite known in nature. Under vacuum, it transforms in a few seconds to a 3D zeolite framework. The latter has a much reduced unit-cell paramater c, 25.586(3) â«.
A C-centered monoclinic polymorph with parameters a = 23.8(5), b = 25.8(5), c = 15.9(3) Ă , ÎČ = 99.5°, and space group Cm was also found by electron diffraction (Mugnaioli et al., 2020).
Cowlesite can be visually similar to thomsonite, but distinguished by surface characteristics and cleavage. Vug linings of thomsonite appear smooth due to the flat crystal terminations. In contrast, linings of cowlesite appear rough, under 30x magnification, due to sharply pointed blades. In addition, thomsonite intergrowths are tough and relatively hard, while cowlesite intergrowths are easily cleaved and soft, similar to gypsum.
Unlike other zeolites, cowlesite has a very limited compositional range (Vezzalini et al., 1992).
The crystal structure resisted its determination by X-ray diffraction methods for a very long time, and only in 2020 the structure could be finally solved by electron diffraction under cryo conditions (Mugnaioli et al., 2020).
Cowlesite is the only two-dimensional (2D) zeolite known in nature. Under vacuum, it transforms in a few seconds to a 3D zeolite framework. The latter has a much reduced unit-cell paramater c, 25.586(3) â«.
A C-centered monoclinic polymorph with parameters a = 23.8(5), b = 25.8(5), c = 15.9(3) Ă , ÎČ = 99.5°, and space group Cm was also found by electron diffraction (Mugnaioli et al., 2020).
Cowlesite can be visually similar to thomsonite, but distinguished by surface characteristics and cleavage. Vug linings of thomsonite appear smooth due to the flat crystal terminations. In contrast, linings of cowlesite appear rough, under 30x magnification, due to sharply pointed blades. In addition, thomsonite intergrowths are tough and relatively hard, while cowlesite intergrowths are easily cleaved and soft, similar to gypsum.
Unique Identifiers
Mindat ID:
1145
Long-form identifier:
mindat:1:1:1145:3
GUID
(UUID V4):
(UUID V4):
00c32d5e-d5e4-4c1a-a0e2-58f5fe02e713
IMA Classification of Cowlesite
Approved
IMA Formula:
Ca(Al2Si3)O10 · 5-6H2O
First published:
1975
Classification of Cowlesite
9.GG.05
9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H2O; zeolite family
G : Unclassified zeolites
9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H2O; zeolite family
G : Unclassified zeolites
77.1.5.8
77 : TECTOSILICATES Zeolites
1 : Zeolite group - True zeolites
77 : TECTOSILICATES Zeolites
1 : Zeolite group - True zeolites
16.9.28
16 : Silicates Containing Aluminum and other Metals
9 : Aluminosilicates of Ca
16 : Silicates Containing Aluminum and other Metals
9 : Aluminosilicates of Ca
Mineral Symbols
As of 2021 there are now IMAâCNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
Symbol | Source | Reference |
---|---|---|
Cow | IMAâCNMNC | Warr, L.N. (2021). IMAâCNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Cowlesite
Vitreous, Greasy
Transparency:
Transparent
Colour:
Colourless, white
Streak:
White
Hardness:
5 - 5½ on Mohs scale
Tenacity:
Brittle
Cleavage:
Perfect
{010}
{010}
Density:
2.14(2) g/cm3 (Measured) 2.05 g/cm3 (Calculated)
Optical Data of Cowlesite
Type:
Biaxial (-)
RI values:
nα = 1.505 - 1.513 nβ = 1.509 - 1.516 nγ = 1.509 - 1.518
2V:
Measured: 44° to 53°
Max Birefringence:
δ = 0.004 - 0.005
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
and does not take into account mineral colouration.
Surface Relief:
Low
Dispersion:
none
Optical Extinction:
X = a; Y = b; Z = c.
Chemistry of Cowlesite
Mindat Formula:
CaAl2Si3O10 · 6H2O
Common Impurities:
Fe,Na,K
Crystallography of Cowlesite
Crystal System:
Orthorhombic
Class (H-M):
mmm (2/m 2/m 2/m) - Dipyramidal
Cell Parameters:
a = 23.116(8) Å, b = 24.891(7) Å, c = 30.468(2) Å
Ratio:
a:b:c = 0.929 : 1 : 1.224
Unit Cell V:
17,530.69 Ă
Âł (Calculated from Unit Cell)
Morphology:
Type material:
Simple blades, showing only three forms: {010}, {001}, and {101}. Crystals can exceed 0.3 mm in length and 0.1 mm in width, but thicknesses are less than 2 ÎŒm.
Simple blades, showing only three forms: {010}, {001}, and {101}. Crystals can exceed 0.3 mm in length and 0.1 mm in width, but thicknesses are less than 2 ÎŒm.
Comment:
Space group Ccme (non-standard setting of space group Cmce). Originally reported cell: a 11.27, b 15.25, c 12.61 â«. Originally, a doubled cell with a 23.3, b 30.6, c 25.0 A is also reported (Vezzalini et al., 1992); this was later found to be the true cell..
X-Ray Powder Diffraction
Powder Diffraction Data:
d-spacing | Intensity |
---|---|
15.2 Ă | (100) |
3.81 Ă | (35) |
2.964 Ă | (35) |
2.934 Ă | (25) |
3.052 Ă | (20) |
5.08 Ă | (17) |
7.62 Ă | (15) |
Comments:
The perfect cleavage makes it impossible to obtain a suitable XRD powder by ordinary grinding with a mortar and pestle.
Geological Environment
Paragenetic Mode(s):
Paragenetic Mode | Earliest Age (Ga) |
---|---|
Near-surface Processes | |
22 : Hydration and low-đ subsurface aqueous alteration (see also #23) |
Type Occurrence of Cowlesite
Co-Type Localities:
â Monte Lake, Kamloops Mining Division, British Columbia, Canada
â Unnamed wash, adjacent to State Route 177, Superior area, Pinal County, Arizona, USA
â North Table Mountain, Golden, Golden Mining District, Jefferson County, Colorado, USA
â Neer Road, Goble, Columbia County, Oregon, USA
â Beech Creek Quarry, Mount Vernon, Grant County, Oregon, USA
â Unnamed wash, adjacent to State Route 177, Superior area, Pinal County, Arizona, USA
â North Table Mountain, Golden, Golden Mining District, Jefferson County, Colorado, USA
â Neer Road, Goble, Columbia County, Oregon, USA
â Beech Creek Quarry, Mount Vernon, Grant County, Oregon, USA
General Appearance of Type Material:
Sometimes visually similar to thomsonite. Thin cavity linings, to 0.5 mm thick, growing as radially oriented blades. As sprays of blades up to 2 mm, and rarely as sprays of delicate, single blades. Blades always < 2 ÎŒm thick.
Place of Conservation of Type Material:
University of California, Santa Barbara, California, USA, 6720, 6721.
National Museum of Natural History, Washington, D.C., USA, 135026.
National Museum of Natural History, Washington, D.C., USA, 135026.
Geological Setting of Type Material:
In amygdules in basalt. Also in scoria.
Associated Minerals at Type Locality:
Reference:
Wise, W.S. and Tschernich, R.W. (1975) Cowlesite, a new Ca-zeolite: American Mineralogist, 60, 951-956.
Synonyms of Cowlesite
Other Language Names for Cowlesite
Relationship of Cowlesite to other Species
Member of:
Other Members of this group:
Alflarsenite | NaCa2Be3Si4O13(OH) · 2H2O | Mon. 2 : P21 |
Amicite | K2Na2Al4Si4O16 · 5H2O | Mon. 2 |
Ammonioleucite | (NH4)(AlSi2O6) | Tet. 4/m : I41/a |
Analcime | Na(AlSi2O6) · H2O | Tric. 1 : P1 |
Bellbergite | (K,Ba,Sr)2Sr2Ca2(Ca,Na)4[Al3Si3O12]6 · 30H2O | Hex. |
Bikitaite | LiAlSi2O6 · H2O | Tric. 1 : P1 |
Boggsite | Ca8Na3(Si,Al)96O192 · 70H2O | Orth. mmm (2/m 2/m 2/m) : Imma |
Brewsterite Subgroup | Zeolite Group. | |
Chabazite-Levyne Subgroup | M[Al2Si4O12] · 6H2O | |
Chiavennite | CaMnBe2Si5O13(OH)2 · 2H2O | Mon. 2/m : P21/b |
Clinoptilolite Subgroup | M3-6(Si30Al6)O72 · 20H2O | |
Dachiardite Subgroup | Zeolite Group. | |
Direnzoite | NaK6MgCa2(Al13Si47O120) · 36H2O | Orth. mmm (2/m 2/m 2/m) : Pmmn |
Edingtonite | Ba[Al2Si3O10] · 4H2O | Orth. 2 2 2 : P21 21 21 |
Epistilbite | CaAl2Si6O16 · 5H2O | Mon. |
Erionite Subgroup | M2[Al4Si14O36] · 15H2O | |
Faujasite Subgroup | M3.5[Al7Si17O48] · 32H2O | |
Ferrierite Subgroup | Zeolite Group. | |
Ferrochiavennite | Ca1-2Fe[(Si,Al,Be)5Be2O13(OH)2] · 2H2O | Mon. 2/m : P21/b |
Flörkeite | (K3Ca2Na)[Al8Si8O32] · 12H2O | Tric. 1 : P1 |
Garronite Subgroup | ||
Gaultite | Na4Zn2Si7O18 · 5H2O | Orth. mm2 : Fdd2 |
Gismondine Subgroup | Zeolite Group. | |
Gmelinite Subgroup | In 1997, gmelinite was split into Gmelinite-Ca, Gmelinite-Na and Gmelinite-K. | |
Gobbinsite | Na5(Si11Al5)O32 · 11H2O | Orth. mmm (2/m 2/m 2/m) : Pnma |
Goosecreekite | Ca[Al2Si6O16] · 5H2O | Mon. 2 : P21 |
Gottardiite | Na3Mg3Ca5Al19Si117O272 · 93H2O | Orth. mmm (2/m 2/m 2/m) : Cmca |
Heulandite Subgroup | (Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O | |
Hsianghualite | Ca3Li2(Be3Si3O12)F2 | Iso. 4 3 2 : I41 3 2 |
Kirchhoffite | Cs(BSi2O6) | Tet. 4/mmm (4/m 2/m 2/m) : I41/acd |
Laumontite | CaAl2Si4O12 · 4H2O | Mon. 2/m : B2/m |
Loomisite | Ba[Be2P2O8] · H2O | Mon. m |
Lovdarite | K2Na6Be4Si14O36 · 9H2O | Orth. mm2 |
Maricopaite | Pb7Ca2(Si,Al)48O100 · 32H2O | Orth. |
Martinandresite | Ba2(Al4Si12O32) · 10H2O | Orth. mmm (2/m 2/m 2/m) : Pmmn |
Mazzite Subgroup | Zeolite Group. | |
Merlinoite | (K,Na)5(Ca,Ba)2Al9Si23O64 · 23H2O | Orth. mmm (2/m 2/m 2/m) : Immm |
Montesommaite | (K,Na)9Al9Si23O64 · 10H2O | Orth. mm2 : Fdd2 |
Mordenite | (Na2,Ca,K2)4(Al8Si40)O96 · 28H2O | Orth. |
Mutinaite | Na3Ca4Si85Al11O192 · 60H2O | Orth. mmm (2/m 2/m 2/m) : Pnma |
Nabesite | Na2BeSi4O10 · 4H2O | Orth. 2 2 2 : P21 21 21 |
Natrolite Subgroup | A subgroup of the Zeolite Group. | |
Offretite | KCaMg(Si13Al5)O36 · 15H2O | Hex. 6 m2 : P6m2 |
Pahasapaite | Li8(Ca,Li,K)10.5Be24(PO4)24 · 38H2O | Iso. 2 3 : I2 3 |
Parthéite | Ca2(Si4Al4) O15 (OH)2 · 4H2O | Mon. 2/m : B2/b |
Paulingite Subgroup | Paulingite was originally described in 1960. | |
Perlialite | K9Na(Ca,Sr)[Al2Si4O12]6 · 15H2O | Hex. 6/mmm (6/m 2/m 2/m) : P6/mmm |
Phillipsite Subgroup | Zeolite Group. | |
Pollucite | (Cs,Na)2(Al2Si4O12) · 2H2O | Iso. m3m (4/m 3 2/m) : Ia3d |
Roggianite | Ca2Be(OH)2Al2Si4O13 · 2.5H2O | Tet. 4/mmm (4/m 2/m 2/m) : I4/mcm |
Stilbite Subgroup | M6-7[Al8-9Si27-28O72] · nH2O | |
Terranovaite | (Na,Ca)8(Si68Al12)O160 · 29H2O | Orth. |
Thomsonite Subgroup | The large majority of "thomsonite" is thomsonite-Ca. | |
Tschernichite | (Ca,Na2)[Al2Si4O12] · 4-8H2O | Tet. 4/mmm (4/m 2/m 2/m) : P4/mmm |
Tschörtnerite | Ca4(Ca,Sr,K,Ba)3Cu3[Al3Si3O12]4(OH)8 · nH2O | Iso. m3m (4/m 3 2/m) : Fm3m |
UM1996-38-SiO:AlCaHNa | Na-Ca-Al-Si-O-H | |
UM1999-33-SiO:AlHKNa | K7Na5Al12Si20O64 · 24H2O | |
UM2002-40-SiO:AlCaHKMgNa | (Mg,Ca,Na,K)7.5(Al12.8Si51.2)O128 · 65H2O | Tet. 4 2 2 : P41 2 2 |
Unnamed (Ca analogue of Merlinoite) | (Ca,K,Na)5(Ca,Ba)2Al9Si23O64 · 23H2O ? | |
Wairakite | Ca(Al2Si4O12) · 2H2O | Mon. 2/m : B2/m |
Weinebeneite | CaBe3(PO4)2(OH)2 · 4H2O | Mon. m : Bb |
Wenkite | (Ba,K)4(Ca,Na)6[(Si,Al)20O39(OH)2](SO4)3 · 0.5H2O | Hex. 6 m2 : P62m |
Willhendersonite | KCa[Al3Si3O12] · 5H2O | Tric. 1 : P1 |
Yugawaralite | CaAl2Si6O16 · 4H2O | Mon. m : Pb |
Common Associates
Associated Minerals Based on Photo Data:
32 photos of Cowlesite associated with Calcite | CaCO3 |
30 photos of Cowlesite associated with Heulandite Subgroup | (Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O |
28 photos of Cowlesite associated with Smectite Group | A0.3D2-3[T4O10]Z2 · nH2O |
26 photos of Cowlesite associated with Thomsonite-Ca | NaCa2[Al5Si5O20] · 6H2O |
21 photos of Cowlesite associated with LĂ©vyne | |
20 photos of Cowlesite associated with Analcime | Na(AlSi2O6) · H2O |
16 photos of Cowlesite associated with Chabazite | |
11 photos of Cowlesite associated with Lévyne-Ca | (Ca,Na2,K2)[Al2Si4O12] · 6H2O |
9 photos of Cowlesite associated with Phillipsite Subgroup | |
7 photos of Cowlesite associated with Offretite | KCaMg(Si13Al5)O36 · 15H2O |
Related Minerals - Strunz-mindat Grouping
9.GG.10 | Mountainite | KNa2Ca2[Si8O19(OH)] · 6H2O |
Other Information
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 Cowlesite
mindat.org URL:
https://www.mindat.org/min-1145.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
References for Cowlesite
Reference List:
Wise, William S., Tschernich, Rudy W. (1975) Cowlesite a new Ca-zeolite. American Mineralogist, 60 (11-12) 951-956
Nawaz, Rab (1984) New data on cowlesite from Northern Ireland. Mineralogical Magazine, 48 (349) 565-566 doi:10.1180/minmag.1984.048.349.19
Tschernich, Rudy W. (1992) Zeolites of the World. Geoscience Press, Inc., Phoenix, Arizona. 567pp.pp.121-128
Coombs, Douglas S., Alberti, Alberto, Armbruster, Thomas, Artioli, Gilberto, Colella, Carmine, Galli, Ermanno, Grice, Joel D., Liebau, Friedrich, Mandarino, Joseph A., Minato, Hideo, Nickel, Ernest H., Passaglia, Elio, Peacor, Donald R., Quartieri, Simona, Rinaldi, Romano, Ross, Malcolm I., Sheppard, Richard A., Tillmanns, Ekkehart, Vezzalini, Giovanna (1997) Recommended nomenclature for zeolite minerals; report of the Subcommittee on Zeolites of the International Mineralogical Association, Commission on New Minerals and Mineral Names. The Canadian Mineralogist, 35 (6) 1571-1606
Localities for Cowlesite
Locality List
- This locality has map coordinates listed.
- This locality has estimated coordinates.
â - 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.
All localities listed without proper references should be considered as questionable.
Antarctica | |
| AmMin 82:423 +1 other reference |
| Mozer (2012) |
Australia | |
| Graham et al. (2002) |
| Haupt (1989) +1 other reference |
| Tschernich (1992) |
Austria | |
| Exel (1993) |
Canada | |
| Tschernich (1992) |
| Mineralogist +3 other references |
| Tschernich (1992) |
| Tschernich (1992) |
| Tschernich (1992) +1 other reference |
Costa Rica | |
| RodrĂguez et al. (2017) |
| Micro Probe Vol 7 No. 7 Spring 1993 |
| Micro Probe Vol. 7 No. 7 Spring 1993 |
| ZeledĂłn (2004) |
| Micro Probe Volume VII Number 7 Spring ... +1 other reference |
ZeledĂłn (2004) | |
Czech Republic | |
| Ing. O. JaneÄek - New localities of ... |
| Personal reference Libor HrĆŻzek |
| PauliĆĄ et al. (2014) |
L.HrĆŻzek | |
| L.HrĆŻzek-Personal reference |
| PauliĆĄ et al. (2018) |
PauliĆĄ et al. (2018) | |
| Petr Fuchs 2007 |
Levyn a dalĆĄĂ zeolity z Hackenbergu u ... | |
PauliĆĄ et al. (2015) +1 other reference | |
| PauliĆĄ et al. (2017) |
| L.HrĆŻzek +1 other reference |
O.JaneÄek | |
L.HrĆŻzek +1 other reference | |
| L.HrĆŻzek |
| RychlĂœ |
Faroe Islands | |
| Tschernich (1992) |
| Betz (1981) +1 other reference |
Germany | |
| Keck (1993) |
Hungary | |
| GEODA 2005/3 +1 other reference |
Iceland | |
Selbekk et al. (2004) | |
| Zeolite collection of Volker Betz |
| Zeolite collection of Volker Betz |
| Betz (1981) |
| Alessandro Cantamessa collection & ... |
| Zeolite collection of Volker Betz |
Italy | |
| Bortolozzi et al. (2007) |
| Bortolozzi et al. (2007) |
Japan | |
| Fujimoto et al. (1990) |
| Yamada (2004) |
| Matsubara (1978) |
New Zealand | |
| Collection of RJ Martin correlated to ... |
| Zeolites of the Word by Rudy ... |
| Thornton (Ed.) |
| J. Thornton. Zeolites and other minerals on Middlehurst Station. Essence of Microscope (NZ) |
Essence of Micro-Scope | |
| Collection of RJ Martin |
| Railton et al. (1990) |
| NZ Zeolite list and locations. Neville ... |
Collection of Rod Martin | |
Russia | |
| ... |
Spain | |
| Lapis 2001 et al. (reference via Ferdinando Giovine) +1 other reference |
UK | |
| Trevor Boyd Collection |
Trevor Boyd Collection | |
| Trevor Boyd Collection |
n° 322 +4 other references | |
rruff.geo.arizona.edu (n.d.) +2 other references | |
| Trevor Boyd (Ferdinando Giovine collection) |
| www.habitas.org.uk (n.d.) |
| Artioli et al. (1994) |
| Zeolite colletion of Volker Betz |
| Trevor Boyd Collection +1 other reference |
| Green et al. (1996) |
| Day (1999) |
USA | |
| Luetcke (n.d.) |
| Wise et al. (1975) +1 other reference |
| Rocks & Minerals 79: 4. +1 other reference |
Jason Evans Collection | |
Wilson (1988) | |
| Ream (1995) |
| Ream (2004) |
| MarekC Collection June 2017 |
| Micro Probe Vol. 6 No. 5 Fall 1987 +2 other references |
| Mineralogist +3 other references |
| Tschernich (1992) |
| Micro Probe Volume VII Number 8 Fall ... |
Micro Probe Volume VII Number 8 Fall ... | |
| K. Starnes |
| Micro Probe Vol. 7 No. 9 Spring 1994 +1 other reference |
| Micro Probe Volume VI Number 4 |
| Micro Probe Vol. 6 No. 4 +1 other reference |
Micro Probe VolumeVII Number 3 Spring ... | |
Rudy Tschernich Zeolite Collection | |
| Micro Probe Volume VI Number 4 |
| Micro Probe Vol. 7 No. 10 |
| Rudy Tschernich Zeolite Collection |
Micro Probe Vol. 7 No. 5 Spring '92 | |
| Wise et al. (1975) +1 other reference |
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Oisgill Bay, Dunvegan, Duirinish, Isle of Skye, Eilean ĂĄ ChĂšo, Highland, Scotland, UK