Ríosecoite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
Formula:
Ca2Mg(AsO3OH)3(H2O)2
Colour:
Colorless
Lustre:
Vitreous
Hardness:
3½
Specific Gravity:
3.24
Crystal System:
Triclinic
Name:
Named for Caleta Río Seco near the type locality of Torrecillas Hill, Chile, and for the small town of Río Seco.
Type Locality:
New structure type
Unique Identifiers
Mindat ID:
52989
Long-form identifier:
mindat:1:1:52989:3
GUID
(UUID V4):
(UUID V4):
0daaecd6-14e1-4f29-8dd2-287bcca94be4
IMA Classification of Ríosecoite
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 Ríosecoite
8.CF.20
8 : PHOSPHATES, ARSENATES, VANADATES
C : Phosphates without additional anions, with H2O
F : With large and medium-sized cations, RO4:H2O > 1:1
8 : PHOSPHATES, ARSENATES, VANADATES
C : Phosphates without additional anions, with H2O
F : With large and medium-sized cations, RO4:H2O > 1:1
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 |
|---|---|---|
| Rse | 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 Ríosecoite
Vitreous
Transparency:
Transparent
Colour:
Colorless
Streak:
White
Hardness:
3½ on Mohs scale
Tenacity:
Brittle
Cleavage:
Perfect
{010} and {001}
{010} and {001}
Fracture:
Step-Like
Density:
3.24(2) g/cm3 (Measured) 3.243 g/cm3 (Calculated)
Optical Data of Ríosecoite
Type:
Biaxial (-)
RI values:
nα = 1.637(1) nβ = 1.651(1) nγ = 1.664(1)
2V:
Measured: 88° (1), Calculated: 87.2°
Max Birefringence:
δ = 0.027
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:
Moderate
Dispersion:
distinct, r< v
Pleochroism:
Non-pleochroic
Comments:
X^b≈18°, Y^a≈10°, Z^c≈48°
Chemistry of Ríosecoite
Mindat Formula:
Ca2Mg(AsO3OH)3(H2O)2
Crystallography of Ríosecoite
Crystal System:
Triclinic
Class (H-M):
1 - Pedial
Space Group:
P1
Cell Parameters:
a = 6.8110(9) Å, b = 7.316(1) Å, c = 11.777(2) Å
α = 83.466(6)°, β = 84.394(6)°, γ = 79.779(6)°
α = 83.466(6)°, β = 84.394(6)°, γ = 79.779(6)°
Ratio:
a:b:c = 0.931 : 1 : 1.61
Unit Cell V:
571.97 ų (Calculated from Unit Cell)
Morphology:
Prisms, elongated and striated on [100] with irregular terminations that commonly come to a somewhat rounded point. Prism forms {010} and {001} were observed. The prisms are often intergrown in subparallel bundles.
Twinning:
None observed
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 7.18 Å | (36) |
| 4.239 Å | (35) |
| 3.578 Å | (100) |
| 3.361 Å | (41) |
| 3.142 Å | (43) |
| 3.006 Å | (48) |
| 2.914 Å | (28) |
| 2.784 Å | (71) |
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 Ríosecoite
Place of Conservation of Type Material:
In the mineralogical collections of the Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA, catalogue number 67257
Associated Minerals at Type Locality:
Reference:
Kampf, A.R., Nash, B.P., Celestian, A.J., Dini, M., and Molina Donoso, A.A. (2019) Camanchacaite, chinchorroite, espadaite, magnesiofluckite, picaite and ríosecoite: six new hydrogen-arsenate minerals from the Torrecillas mine, Iquique Province, Chile. Mineralogical Magazine: 83: 655-671.
Synonyms of Ríosecoite
Related Minerals - Strunz-mindat Grouping
| 8.CF. | Naalasite | NaAl(AsO3OH)2 · H2O |
| 8.CF. | Falsterite | Ca2MgMn2+2Fe2+2Fe3+2Zn4(PO4)8(OH)4(H2O)14 |
| 8.CF. | Ferraioloite | MgMn2+4(Fe2+0.5Al3+0.5)4Zn4(PO4)8(OH)4(H2O)20 |
| 8.CF. | Espadaite | Na4Ca3Mg2[AsO3(OH)]2[AsO2(OH)2]10 · 7H2O |
| 8.CF. | Liraite | NaCa2Mn2+2[Fe3+Fe2+]Mn2+2(PO4)6(H2O)2 |
| 8.CF. | Nafeasite | Na3Fe3+3(AsO3OH)6 · 3H2O |
| 8.CF.05 | Grischunite | NaCa2Mn2+5Fe3+(AsO4)6 · 2H2O |
| 8.CF.05 | Wicksite | NaCa2(Fe2+,Mn2+)4MgFe3+(PO4)6 · 2H2O |
| 8.CF.05 | Bederite | Ca2(Mn2+)4(Fe3+)2(PO4)6 · 2H2O |
| 8.CF.05 | Tassieite | (Na,◻)Ca2(Mg,Fe2+,Fe3+)2(Fe2+,Mg)2(Fe3+,Mg)2(PO4)6 · 2H2O |
| 8.CF.05 | Maneckiite | (Na◻)Ca2Fe2+2(Fe3+Mg)Mn2(PO4)6 · 2H2O |
| 8.CF.10 | Haigerachite | KFe3+3(PO3OH)2[PO2(OH)2]6 · 4H2O |
| 8.CF.10 | Yazganite | NaFe3+2(Mg,Mn2+)(AsO4)3 · H2O |
| 8.CF.15 | Currierite | Na4Ca3MgAl4(AsO3OH)12 · 9H2O |
Fluorescence of Ríosecoite
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 Ríosecoite
mindat.org URL:
https://www.mindat.org/min-52989.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 Ríosecoite
Reference List:
Hålenius, U., Hatert, F., Pasero, M., Mills, S. J. (2018) CNMNC Newsletter No. 44, New minerals and nomenclature modifications approved in 2018. Mineralogical Magazine, 82 (4) 1015-1021 doi:10.1180/mgm.2018.148
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 Ríosecoite
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 NavTopUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsStrunz-MindatFluorescence Other InformationInternet Links References Localities Locality List
