Chongite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Chongite
Formula:
Ca3Mg2(AsO4)2(AsO3OH)2 · 4H2O
Lustre:
Vitreous
Hardness:
3½
Specific Gravity:
3.09
Crystal System:
Monoclinic
Member of:
Name:
Honours Dr. Guillermo Chong Díaz (born 1936). Dr. Chong is a prominent Chilean geologist and academician whose research has largely focused on the Atacama Desert. During his approximately 50-year career, he has some 250 publications and meeting presentations, including serving as lead author for the chapter on Industrial Minerals and Rocks in The Geology of Chile published by the Geological Society of London in 2007. Dr. Chong is currently a professor in the Department of Geological Sciences at Universidad Católica del Norte in Antofagasta, Chile.
The Mg analogue of sainfeldite. Chemically related to irhtemite and picropharmacolite; also similar to adelite, camgasite, talmessite, and wendwilsonite.
See also UM1997-09-AsO:CaHMgZn which is probably identical to chongite.
See also UM1997-09-AsO:CaHMgZn which is probably identical to chongite.
Unique Identifiers
Mindat ID:
46711
Long-form identifier:
mindat:1:1:46711:3
Similar Names
| Shungite (1) | A variety of 'Pyrobitumen' |
| Shungite (2) | A rock subtype |
IMA Classification of Chongite
Approved
IMA Formula:
Ca3Mg2(As5+O4)2(As5+O3OH)2·4H2O
Approval year:
2015
First published:
2016
Classification of Chongite
8.00.
8 : PHOSPHATES, ARSENATES, VANADATES
0 :
0 :
8 : PHOSPHATES, ARSENATES, VANADATES
0 :
0 :
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 |
|---|---|---|
| Cng | 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 Chongite
Vitreous
Transparency:
Transparent
Streak:
White
Hardness:
3½ on Mohs scale
Tenacity:
Brittle
Cleavage:
Distinct/Good
on {100}
on {100}
Fracture:
Conchoidal
Density:
3.09 g/cm3 (Measured) 3.087 g/cm3 (Calculated)
Optical Data of Chongite
Type:
Biaxial (-)
RI values:
nα = 1.612(1) nβ = 1.626(1) nγ = 1.635(1)
2V:
Measured: 76.9° , Calculated: 76.9°
Max. Birefringence:
δ = 0.023
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
Dispersion:
r & lt; v, distinct
Pleochroism:
Non-pleochroic
Chemistry of Chongite
Mindat Formula:
Ca3Mg2(AsO4)2(AsO3OH)2 · 4H2O
Element Weights:
Common Impurities:
Mn
Crystallography of Chongite
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
B2/b
Setting:
C2/c
Cell Parameters:
a = 18.5879(6) Å, b = 9.3660(3) Å, c = 9.9622(7) Å
β = 96.916(7)°
β = 96.916(7)°
Ratio:
a:b:c = 1.985 : 1 : 1.064
Unit Cell V:
1721.75 ų
Z:
4
Morphology:
Prismatic crystals; tightly intergrown radial aggregates
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 8.35 Å | (29) |
| 4.644 Å | (62) |
| 4.396 Å | (26) |
| 3.372 Å | (62) |
| 3.275 Å | (100) |
| 3.113 Å | (57) |
| 2.384 Å | (30) |
| 1.799 Å | (22) |
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Stage 7: Great Oxidation Event | <2.4 |
| 47a : [Near-surface hydration of prior minerals] | |
| 47d : [Arsenates, antimonates, selenates, bismuthinates] | |
| Stage 10b: Anthropogenic minerals | <10 Ka |
| 55 : Anthropogenic mine minerals |
Type Occurrence of Chongite
General Appearance of Type Material:
Prismatic crystals to about 1 mm in length grouped in tightly intergrown radial aggregates to about 2 mm in diameter
Place of Conservation of Type Material:
Co-type material is deposited in the mineralogical collections of the Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA, catalogue numbers 65585, 65586 and 65587
Geological Setting of Type Material:
Veins rich in secondary arsenic and copper minerals that intersect metamorphosed marine shales and lavas. Formed from the oxidation of native arsenic and other As-bearing primary phases, followed by later alteration by saline fluids derived from evaporating meteoric water under hyperarid conditions.
Associated Minerals at Type Locality:
Synonyms of Chongite
Other Language Names for Chongite
Relationship of Chongite to other Species
Member of:
Other Members of Hureaulite Group:
| Giftgrubeite | CaMn2Ca2(AsO4)2(AsO3OH)2 · 4H2O | Mon. 2/m : B2/b |
| Hureaulite | Mn2+5(PO3OH)2(PO4)2 · 4H2O | Mon. 2/m : B2/b |
| Miguelromeroite | Mn2+5(AsO3OH)2(AsO4)2(H2O)4 | Mon. 2/m : B2/b |
| Nyholmite | Cd3Zn2(AsO3OH)2(AsO4)2 · 4H2O | Mon. 2/m : B2/b |
| Sainfeldite | Ca5(AsO4)2(AsO3OH)2 · 4H2O | Mon. 2/m : B2/b |
| Villyaellenite | (Mn,Ca)Mn2Ca2(AsO3OH)2(AsO4)2 · 4H2O | Mon. 2/m : B2/b |
Common Associates
Associations Based on Photo Data:
| 3 photos of Chongite associated with Picropharmacolite | Ca4Mg(AsO4)2(HAsO4)2 · 11H2O |
Related Minerals - Strunz-mindat Grouping
| 8.00. | Canutite | NaMn3[AsO4][AsO3(OH)]2 |
| 8.00. | Metauramphite | (NH4)2(UO2)2(PO4)2.6H2O |
| 8.00. | Strontiohurlbutite | SrBe2(PO4)2 |
| 8.00. | Grandaite | Sr2Al(AsO4)2(OH) |
| 8.00. | 'UM1997-10-AsO:CaV' | Ca(VO)2(AsO4)2.4H2O |
| 8.00.05 | 'Leobenite' | Hydrated Ca-Fe phosphate |
Other Information
Notes:
Slowly soluble in dilute HCl at room temperature.
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 Chongite
mindat.org URL:
https://www.mindat.org/min-46711.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 Chongite
Reference List:
Hålenius, U., Hatert, F., Pasero, M., Mills, S. J. (2015) New minerals and nomenclature modifications approved in 2015, CNMNC Newsletter 26. Mineralogical Magazine, 79 (4) 941-947 doi:10.1180/minmag.2015.079.4.05
Localities for Chongite
Showing 5 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.
Chile | |
| Gerhard Möhn Collection. Identified by ... |
| Hålenius et al. (2015) +1 other reference |
Czech Republic | |
| Kampf et al. (2016) |
France | |
| Meisser et al. (2019) |
Germany | |
| Möhn |
Quick NavTopAbout ChongiteUnique IdentifiersSimilar NamesIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesRelationshipsCommon AssociatesStrunz-MindatOther InformationInternet Links References Localities Locality List
Geschieber vein, Svornost Mine, Jáchymov, Karlovy Vary District, Karlovy Vary Region, Czech Republic