Chinchorroite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Chinchorroite
Formula:
Na2Mg5(As2O7)2(AsO3OH)2(H2O)10
Colour:
Colorless
Lustre:
Vitreous
Hardness:
2½
Specific Gravity:
2.75
Crystal System:
Triclinic
Name:
Named for the Chinchorro inhabitants of the coastal region of northern Chile and southern Peru from 9,000 to 3,500 years BP including the area around the type locality. The Chinchorro people are best known for their burial practices, including mummification. Hair samples show that they suffered from arsenic poisoning likely due to contaminated water.
New structure type.
Unique Identifiers
Mindat ID:
52884
Long-form identifier:
mindat:1:1:52884:9
IMA Classification of Chinchorroite
Approved
Approval year:
2018
First published:
2019
Type description reference:
Kampf, Anthony R., Nash, Barbara P., Celestian, Aaron J., Dini, Maurizio, Molina Donoso, Arturo A. (2019) Camanchacaite, chinchorroite, espadaite, magnesiofluckite, picaite and ríosecoite: six new hydrogen-arsenate minerals from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine, 83 (5) 655-671 doi:10.1180/mgm.2019.28
Classification of Chinchorroite
8.FD.15
8 : PHOSPHATES, ARSENATES, VANADATES
F : Polyphosphates, Polyarsenates, [4]-Polyvanadates
D : Polyphosphates, etc., with OH and H2O
8 : PHOSPHATES, ARSENATES, VANADATES
F : Polyphosphates, Polyarsenates, [4]-Polyvanadates
D : Polyphosphates, etc., with OH and H2O
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 |
|---|---|---|
| Cch | 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 Chinchorroite
Vitreous
Transparency:
Transparent
Colour:
Colorless
Streak:
White
Hardness:
2½ on Mohs scale
Tenacity:
Brittle
Cleavage:
Very Good
{100} and {010}
{100} and {010}
Fracture:
Sub-Conchoidal, Step-Like
Density:
2.75(2) g/cm3 (Measured) 2.758 g/cm3 (Calculated)
Optical Data of Chinchorroite
Type:
Biaxial (+)
RI values:
nα = 1.546(2) nβ = 1.560(2) nγ = 1.578(2)
2V:
Measured: 84° (2), Calculated: 83.7°
Max. Birefringence:
δ = 0.032
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.
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:
distinct, r> v inclined
Optical Extinction:
X ∧ a = 4°; Y ∧ b = 52°; Z ∧ c = 20°.
Pleochroism:
Non-pleochroic
Chemistry of Chinchorroite
Mindat Formula:
Na2Mg5(As2O7)2(AsO3OH)2(H2O)10
Element Weights:
Crystallography of Chinchorroite
Crystal System:
Triclinic
Class (H-M):
1 - Pedial
Space Group:
P1
Cell Parameters:
a = 8.7777(2) Å, b = 8.8570(3) Å, c = 9.7981(7) Å
α = 91.097(6)°, β = 110.544(8)°, γ = 103.167(7)°
α = 91.097(6)°, β = 110.544(8)°, γ = 103.167(7)°
Ratio:
a:b:c = 0.991 : 1 : 1.106
Unit Cell V:
690.43 ų (Calculated from Unit Cell)
Morphology:
Blades. Tablets flattened on {001}, elongate on [100] and exhibiting the forms {100}, {010}, {001} and {1-10}.
Twinning:
None observed
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 9.10 Å | (100) |
| 8.63 Å | (54) |
| 5.25 Å | (32) |
| 4.034 Å | (49) |
| 3.521 Å | (35) |
| 3.036 Å | (53) |
| 2.811 Å | (42) |
| 2.568 Å | (36) |
Reference:
Kampf, Anthony R., Nash, Barbara P., Celestian, Aaron J., Dini, Maurizio, Molina Donoso, Arturo A. (2019) Camanchacaite, chinchorroite, espadaite, magnesiofluckite, picaite and ríosecoite: six new hydrogen-arsenate minerals from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine, 83 (5) 655-671 doi:10.1180/mgm.2019.28
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] |
Type Occurrence of Chinchorroite
General Appearance of Type Material:
Blades to about 1 mm in maximum dimension, which occur both isolated and in massive intergrowths.
Place of Conservation of Type Material:
Type material is deposited in the mineralogical collections of the Natural History Museum of Los Angeles County, 900 Exposition Blvd, Los Angeles, California, USA, catalogue number 67257
Associated Minerals at Type Locality:
Reference:
Kampf, Anthony R., Nash, Barbara P., Celestian, Aaron J., Dini, Maurizio, Molina Donoso, Arturo A. (2019) Camanchacaite, chinchorroite, espadaite, magnesiofluckite, picaite and ríosecoite: six new hydrogen-arsenate minerals from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine, 83 (5) 655-671 doi:10.1180/mgm.2019.28
Synonyms of Chinchorroite
Other Language Names for Chinchorroite
Dutch:Chinchorroiet
German:Chinchorroit
Related Minerals - Strunz-mindat Grouping
| 8.FD.05 | Volborthite | Cu3(V2O7)(OH)2 · 2H2O |
| 8.FD.05 | Martyite | Zn3(V2O7)(OH)2 · 2H2O |
| 8.FD.05 | Karpenkoite | Co3(V2O7)(OH)2 · 2H2O |
| 8.FD.10 | Vanarsite | NaCa12(As3+V5+8.5V4+3.5As5+6O51)2 · 78H2O |
| 8.FD.10 | Packratite | Ca11(As3+V5+10V4+2As5+6O51)2 · 83H2O |
| 8.FD.10 | Bicapite | [KNa2Mg2(H2O)25][H2PV5+12O40(V5+O)2] |
| 8.FD.10 | Morrisonite | Ca11(As3+V4+2V5+10As5+6O51)2 · 78H2O |
| 8.FD.10 | Lumsdenite | NaCa3Mg2(As3+V4+2V5+10As5+6O51) · 45H2O |
| 8.FD.10 | Gatewayite | Ca6(As3+V4+3 V5+9As5+6O51) · 31H2O |
| 8.FD.10 | Kegginite | Pb3Ca3[AsV12O40(VO)] · 20H2O |
Fluorescence of Chinchorroite
None
Other Information
Notes:
Easily soluble in dilute HCl.
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 Chinchorroite
mindat.org URL:
https://www.mindat.org/min-52884.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 Chinchorroite
Reference List:
Hålenius, U., Hatert, F., Pasero, M., Mills, S. J. (2018) New minerals and nomenclature modifications approved in 2018. Mineralogical Magazine, 82 (2). 445-451 doi:10.1180/mgm.2018.71p.448
Kampf, Anthony R., Nash, Barbara P., Celestian, Aaron J., Dini, Maurizio, Molina Donoso, Arturo A. (2019) Camanchacaite, chinchorroite, espadaite, magnesiofluckite, picaite and ríosecoite: six new hydrogen-arsenate minerals from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine, 83 (5) 655-671 doi:10.1180/mgm.2019.28
Localities for Chinchorroite
Showing 1 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 (TL) | |
| Kampf et al. (2019) |
Quick NavTopAbout ChinchorroiteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesStrunz-MindatFluorescence Other InformationInternet Links References Localities Locality List
Torrecillas mine, Iquique, Iquique Province, Tarapacá, Chile