Gismondine-Ca
A valid IMA mineral species
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About Gismondine-Ca
Carlo Giuseppe Gismondi (1762-1824)
Formula:
CaAl2Si2O8 · 4H2O
Colour:
Colorless, white, grayish, bluish white, reddish
Lustre:
Vitreous
Hardness:
4½
Specific Gravity:
2.20 - 2.26
Crystal System:
Monoclinic
Member of:
Name:
Named gismondine in 1817 for Carlo Giuseppe Gismondi (1762-1824), Italian mineralogist, who previously discovered "zeagonite" - a mixture of gismondine and phillipsite. The suffix was added by the IMA in 2021, after the discovery of gismondine-Sr. The suffix/modifier follows the naming convention for zeolites and denotes the dominant extra-framework cation.
Nearly all gismondines found and studied over almost two centuries are calcium-dominant.
In 2001, a barium-dominant gismondine, "gismondine-Ba" has been discovered in slag material (of course not approved, as valid species, by IMA CNMNC).
The Ca analogue of gismondine-Sr was approved in 2021.
In 2001, a barium-dominant gismondine, "gismondine-Ba" has been discovered in slag material (of course not approved, as valid species, by IMA CNMNC).
The Ca analogue of gismondine-Sr was approved in 2021.
Unique Identifiers
Mindat ID:
1701
Long-form identifier:
mindat:1:1:1701:1
Similar Names
| Gismondine-Ba | Valid as an unnamed mineral | Ba2Al4Si4O16 · 4-6H2O |
IMA Classification of Gismondine-Ca
Approved
IMA status notes:
Renamed by the IMA
IMA Formula:
Ca2(Si4Al4)O16·8H2O
First published:
1817
Classification of Gismondine-Ca
9.GC.05
9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H2O; zeolite family
C : Chains of doubly-connected 4-membered rings
9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H2O; zeolite family
C : Chains of doubly-connected 4-membered rings
16.9.25
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 IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Gis | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Gismondine-Ca
Vitreous
Transparency:
Transparent, Translucent
Colour:
Colorless, white, grayish, bluish white, reddish
Streak:
White
Hardness:
4½ on Mohs scale
Cleavage:
Distinct/Good
Two poor to distinct cleavages parallel to form {232}.
Two poor to distinct cleavages parallel to form {232}.
Fracture:
Conchoidal, Sub-Conchoidal
Density:
2.20 - 2.26 g/cm3 (Measured) 2.28 g/cm3 (Calculated)
Optical Data of Gismondine-Ca
Type:
Biaxial (-)
RI values:
nα = 1.525 - 1.540 nβ = 1.531 - 1.544 nγ = 1.541 - 1.550
2V:
Measured: 82° to 86°
Max. Birefringence:
δ = 0.010 - 0.016
Based on recorded range of RI values above.
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. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
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. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
Surface Relief:
Moderate
Optical Extinction:
Y = b; Z ∧ c = 42.5°.
Chemistry of Gismondine-Ca
Mindat Formula:
CaAl2Si2O8 · 4H2O
Element Weights:
Crystallography of Gismondine-Ca
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/b
Setting:
P21/c
Cell Parameters:
a = 10.02(3) Å, b = 10.61(5) Å, c = 9.843(15) Å
β = 92.25°
β = 92.25°
Ratio:
a:b:c = 0.944 : 1 : 0.928
Unit Cell V:
1,045.62 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Simple pseudotetragonal dipyramids.
Twinning:
Very common
Epitaxial Relationships of Gismondine-Ca
Epitaxial Minerals:
| Phillipsite Subgroup | (Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O |
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 2.706 Å | (100) |
| 4.25 Å | (70) |
| 3.19 Å | (70) |
| 4.93 Å | (60) |
| 3.13 Å | (60) |
| 7.26 Å | (55) |
| 2.738 Å | (55) |
Type Occurrence of Gismondine-Ca
Synonyms of Gismondine-Ca
Other Language Names for Gismondine-Ca
Relationship of Gismondine-Ca to other Species
Member of:
Other Members of Gismondine Subgroup:
| 'Gismondine-Ba' | Ba2Al4Si4O16 · 4-6H2O | |
| Gismondine-Sr | Sr4(Si8Al8O32) · 9H2O | Orth. 222 : C2221 |
Common Associates
Associations Based on Photo Data:
| 42 photos of Gismondine-Ca associated with Phillipsite Subgroup | (Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O |
| 19 photos of Gismondine-Ca associated with Thomsonite-Ca | NaCa2[Al5Si5O20] · 6H2O |
| 13 photos of Gismondine-Ca associated with Chabazite-Ca | (Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O |
| 9 photos of Gismondine-Ca associated with Tobermorite | Ca5Si6O17 · 5H2O |
| 8 photos of Gismondine-Ca associated with Calcite | CaCO3 |
| 4 photos of Gismondine-Ca associated with Wollastonite | Ca3(Si3O9) |
| 4 photos of Gismondine-Ca associated with Flörkeite | (K3Ca2Na)[Al8Si8O32] · 12H2O |
| 4 photos of Gismondine-Ca associated with Phillipsite-K | K6(Si10Al6)O32 · 12H2O |
| 4 photos of Gismondine-Ca associated with Gyrolite | NaCa16Si23AlO60(OH)8 · 14H2O |
| 3 photos of Gismondine-Ca associated with Willhendersonite | KCa[Al3Si3O12] · 5H2O |
Related Minerals - Strunz-mindat Grouping
| 9.GC. | Gismondine-Sr | Sr4(Si8Al8O32) · 9H2O |
| 9.GC. | Garronite-Na | Na6(Al6Si10O32) · 8.5H2O |
| 9.GC.05 | 'Gismondine-Ba' | Ba2Al4Si4O16 · 4-6H2O |
| 9.GC.05 | Garronite-Ca | Na2Ca5Al12Si20O64 · 27H2O |
| 9.GC.05 | Gobbinsite | Na5(Si11Al5)O32 · 11H2O |
| 9.GC.05 | Amicite | K2Na2Al4Si4O16 · 5H2O |
| 9.GC.10 | Martinandresite | Ba2(Al4Si12O32) · 10H2O |
| 9.GC.10 | Harmotome | Ba2(Si12Al4)O32 · 12H2O |
| 9.GC.10 | Phillipsite-Ca | Ca3(Si10Al6)O32 · 12H2O |
| 9.GC.10 | Phillipsite-K | K6(Si10Al6)O32 · 12H2O |
| 9.GC.10 | Phillipsite-Na | (Na,K,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] · 12H2O |
| 9.GC.10 | Flörkeite | (K3Ca2Na)[Al8Si8O32] · 12H2O |
| 9.GC.15 | Merlinoite | K5Ca2(Si23Al9)O64 · 24H2O |
| 9.GC.20 | Mazzite-Na | Na8[Al4Si14O36]2 · 30H2O |
| 9.GC.20 | Mazzite-Mg | (Mg,K,Ca)5(Si26Al10)O72 · 28H2O |
| 9.GC.25 | Perlialite | K9Na(Ca,Sr)[Al2Si4O12]6 · 15H2O |
| 9.GC.30 | Boggsite | Ca8Na3(Si,Al)96O192 · 70H2O |
| 9.GC.35 | Paulingite-Ca | (Ca,K,Na,Ba, ◻)10 (Si, Al)42O84 · 34H2O |
| 9.GC.35 | Paulingite-K | (K2,Ca,Na2,Ba)5[Al10Si35O90] · 45H2O |
| 9.GC.35 | 'Paulingite-Na' | (Na2,K2,Ca,Ba)5[Al10Si35O90] · 45H2O |
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 Gismondine-Ca
mindat.org URL:
https://www.mindat.org/min-1701.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 Gismondine-Ca
Reference List:
Des Cloizeaux, Alfred (1883) Note sur l'existence de deux axes optiques écartés dans les cristaux de Gismondine. Bulletin de Minéralogie, 6 (9) 301-305 doi:10.3406/bulmi.1883.1836
Des Cloizeaux, Alfred (1884) Nouvelle note sur la Gismondine et sur la Christianite. Bulletin de Minéralogie, 7 (3) 135-139 doi:10.3406/bulmi.1884.2353
Walker, G. P. L. (1962) Low-potash gismondine from Ireland and Iceland. Mineralogical Magazine and Journal of the Mineralogical Society, 33 (258). 187-201 doi:10.1180/minmag.1962.033.258.02
Fischer, Karl (1963) The crystal structure determination of the zeolite, gismondite, CaAl2Si2O8·4H2O. American Mineralogist, 48 (5-6) 664-671
Nawaz, Rab (1980) Morphology, twinning, and optical orientation of gismondine. Mineralogical Magazine, 43 (331) 841-844 doi:10.1180/minmag.1980.043.331.03
Vezzalini, Giovanna, Oberti, Roberta (1984) The crystal chemistry of gismondines : the non-existence of K-rich gismondines. Bulletin de Minéralogie, 107 (6) 805-812 doi:10.3406/bulmi.1984.7822
Artioli, G., Rinaldi, R., Kvick, Å., Smith, J.V. (1986) Neutron diffraction structure refinement of the zeolite gismondine at 15 K. Zeolites, 6 (5) 361-366 doi:10.1016/0144-2449(86)90063-1
Coombs, Douglas S., Alberti, Alberto, Armbruster, Thomas, Artioli, Gilberto, Colella, Carmine, Galli, Ermanno, Grice, Joel D., Liebau, Friedrich, Mandarino, Joseph A., Minato, Hideo, et al. (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 Gismondine-Ca
Showing 51 localities.
symbol to view information about a locality.
The Locality List
- 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).
All localities listed without proper references should be considered as questionable.
Austria | |
| Kolitsch (2008) |
Canada | |
| Van Velthuizen et al. (2006) |
| Horváth et al. (1990) +1 other reference |
| Tarassoff et al. (2006) |
Czech Republic | |
| P.Pauliš et al. (2014) |
| Rychlý et al. (1980) | |
| |
| Vojtěch Zeman Collection |
France | |
| Lacroix (1893) |
| André MELLE collection - Georges ... |
Germany | |
| https://www.mineralienatlas.de/?l=7371 |
| Hentschel (1983) |
| Hentschel (1987) |
| Peacor et al. (1984) |
| in the collection of Christof Schäfer | |
| Juroszek et al. (Ti 5 Fe) | |
| Hentschel (1983) |
| Hentschel (1975) |
| in the collection of Christof Schäfer | |
| in the collection of Christof Schäfer +1 other reference | |
| in the collection of Christof Schäfer | |
| in the collection of Christof Schäfer |
| Schüller et al. (1986) |
| Hentschel (1983) | |
| Hentschel (1987) |
| Hentschel (1993) |
| Hentschel (1987) |
| Hentschel (1973) +1 other reference |
Israel | |
| Kruszewski et al. (2021) |
| Galuskina et al. (2026) | |
Italy | |
| Russo et al. (2004) +1 other reference |
| Christof Schäfer. +1 other reference |
| Antonio Borrelli collection +1 other reference |
| Joan Rosell-Riba (2023) |
| Wadoski-Romeijn et al. (2013) |
Jordan | |
| Galuskin et al. (2023) |
Mexico | |
| |
New Zealand | |
| Rod Martin personal collection |
| Graham et al. (2003) +1 other reference |
Portugal | |
| Alves (n.d.) |
Romania | |
| Călin et al. (2025) |
Russia | |
| Ivanyuk et al. (2017) +1 other reference |
Spain | |
| Calvo et al. (2013) |
| Calvo et al. (2010) | |
| Calvo et al. (2013) |
UK | |
| Walker (1962) +2 other references |
USA | |
| |
| Iijima et al. (1969) |
| |
| Mineralogical Society of America - ... |
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Graulay quarry, Hillesheim, Gerolstein, Vulkaneifel, Rhineland-Palatinate, Germany