SUPPORT US. Covid-19 has significantly affected our fundraising. Please help!
Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsBooks & Magazines
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral Quiz
Photo SearchPhoto GalleriesSearch by ColorNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryMineral Photography


This page is currently not sponsored. Click here to sponsor this page.
Hide all sections | Show all sections

About FuenzalidaiteHide

Humberto Fuenzalida
K6(Na,K)4Na6Mg10(SO4)12(IO3)12 · 12H2O
Colourless to pale yellow
2 - 3
Crystal System:
Named by Judith A. Konnert, Howard T. Evans, Jr., James J. McGee, and George E. Ericksen in 1994 in honor of Humberto Fuenzalida Villegas (27 March 1904, Curicó, Chile - 24 February 1966, Santiago, Chile), geographer, geologist, paleontologist, academic and naturalist. He was director of the National Museum of Natural History between 1948 and 1964. He founded the Chilean School of Geology within the Faculty of Physical Sciences and Mathematics at the University of Chile (and was the first Director) and the Institute of Geography at the Faculty of Education at the same university. He also co-founded the Antarctic Institute of Chile (INACH) and the Geological Society of Chile.
Isostructural with:
Carlosruizite-Fuenzalidaite Series. The S analogue of carlosruizite.

Occurs in veins and veinlets of the white nitrate ore ("Caliche Blanco").

The structure is based on two complex slabs, normal to the c axis; each slab consists of a double layer formed by trigonal-pyramidal iodate groups, bounded at the top and bottom by layers of SO4 groups. The layers are separated by K, with Na and Mg helding the layer complex together. The structure somewhat resembles that of alunite group members.

Classification of FuenzalidaiteHide

First published:

7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
D : Sulfates (selenates, etc.) with additional anions, with H2O
G : With large and medium-sized cations; with NO3, CO3, B(OH)4, SiO4 or IO3
Dana 7th ed.:

1 : Miscellaneous

Physical Properties of FuenzalidaiteHide

Colourless to pale yellow
2 - 3 on Mohs scale

Optical Data of FuenzalidaiteHide

Uniaxial (-)
RI values:
nω = 1.622 nε = 1.615
Max Birefringence:
δ = 0.007
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
Surface Relief:

Chemical Properties of FuenzalidaiteHide

K6(Na,K)4Na6Mg10(SO4)12(IO3)12 · 12H2O
IMA Formula:
K3Na5Mg5(IO3)6(SO4)6 · 6H2O

Crystallography of FuenzalidaiteHide

Crystal System:
Class (H-M):
3m (3 2/m) - Hexagonal Scalenohedral
Space Group:
Cell Parameters:
a = 9.4643(4) Å, c = 27.336(6) Å
a:c = 1 : 2.888
Unit Cell V:
2,120.52 ų (Calculated from Unit Cell)

Crystal StructureHide

Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Display Options
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
CIF File    Best | x | y | z | a | b | c
Stop | Start
Console Off | On | Grey | Yellow
IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0001677FuenzalidaiteKonnert J A, Evans H T, McGee J J, Ericksen G E (1994) Mineralogical studies of the nitrate deposits of Chile: VII. Two saline minerals with the composition K6(Na,K)4Na6Mg10(XO4)12(IO3)12.12H2O: Fuenzalidaite (X=S) and carloruizite (X=Se) American Mineralogist 79 1003-100819940293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
13.67 Å(50)
7.05 Å(40)
3.927 Å(100)
3.023 Å(41)
2.681 Å(33)

Type Occurrence of FuenzalidaiteHide

General Appearance of Type Material:
thin, euhedral, platy crystals with hexagonal outline, usually less than 200 microns in diameter and 20 microns thick
Geological Setting of Type Material:
veins and veinlets of "caliche blanco"
Associated Minerals at Type Locality:

Synonyms of FuenzalidaiteHide

Other Language Names for FuenzalidaiteHide

Relationship of Fuenzalidaite to other SpeciesHide

Common AssociatesHide

Associated Minerals Based on Photo Data:
2 photos of Fuenzalidaite associated with NitratineNaNO3

Related Minerals - Nickel-Strunz GroupingHide

7.DG.MathesiusiteK5(UO2)4(SO4)4(VO5) · 4H2OTet. 4/m : P4/n
7.DG.05DarapskiteNa3(SO4)(NO3) · H2OMon. 2/m
7.DG.10Clinoungemachite(Na, K, Fe, SO4)Mon. 2/m
7.DG.10HumberstoniteNa7K3Mg2(SO4)6(NO3)2 · 6H2OTrig. 3 : R3
7.DG.10UngemachiteK3Na8Fe(SO4)6(NO3)2 · 6H2OTrig. 3 : R3
7.DG.15BentoriteCa6(Cr3+,Al)2(SO4)3(OH)12 · 26H2OTrig. 3m : P3 1c
7.DG.15CharlesiteCa6(Al,Si)2(SO4)2[B(OH)4](OH,O)12 · 26H2OTrig. 3m : P3 1c
7.DG.15EttringiteCa6Al2(SO4)3(OH)12 · 26H2OTrig. 3m : P3 1c
7.DG.15JouravskiteCa3Mn4+(SO4)(CO3)(OH)6 · 12H2OHex. 6 : P63
7.DG.15SturmaniteCa6(Fe3+,Al,Mn3+)2(SO4)2[B(OH)4](OH)12 · 25H2OTrig. 3m : P3 1c
7.DG.15ThaumasiteCa3(SO4)[Si(OH)6](CO3) · 12H2OHex. 6 : P63
7.DG.15CarraraiteCa3(SO4)[Ge(OH)6](CO3) · 12H2OHex.
7.DG.15BuryatiteCa3(Si,Fe,Al)(SO4)[B(OH)4]O(OH)5 · 12H2OTrig. 3m : P3 1c
7.DG.20RapidcreekiteCa2(SO4)(CO3) · 4H2OOrth.
7.DG.20KorkinoiteCa4(SO4)2(CO3)2 · 9(H2O)Orth. mmm (2/m 2/m 2/m) : Pmmm
7.DG.25TatarskiteCa6Mg2(SO4)2(CO3)2(OH)4Cl4 · 7H2OOrth.
7.DG.30NakauriiteCu8(SO4)4(CO3)(OH)6 · 48H2OOrth.
7.DG.35Chessexite(Na,K)4Ca2(Mg,Zn)3Al8(SO4)10(SiO4)2 · 40H2OOrth.
7.DG.40CarlosruiziteK6(Na,K)4Na6Mg10(SeO4)12(IO3)12 · 12H2OTrig. 3m (3 2/m) : P3c1
7.DG.45Chelyabinskite(Ca,Mg)3(SO4,CO3)2[Si(OH)6] · 9H2O (?)Orth.

Related Minerals - Dana Grouping (8th Ed.)Hide,K)4Na6Mg10(SeO4)12(IO3)12 · 12H2OTrig. 3m (3 2/m) : P3c1

Other InformationHide

Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for FuenzalidaiteHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Konnert, J.A., Evans, H.T.Jr., McGee, J.J., Ericksen, G.E. (1994) Mineralogical studies of the nitrate deposits of Chile: VII. Two new saline minerals with the composition K6(Na,K)4Na6Mg10(XO4)12(IO3)12.l2H2O: Fuenzalidaite (X = S) and carlosruizite (X = Se). American Mineralogist: 79: 1003-1008.
Mandarino, J.A. (1996) Abstracts of New Mineral Descriptions. Mineralogical Record: 27: 202-203.
Mandarino J.A. (1997) New Minerals 1990-1994. The Mineralogical Record Inc.

Internet Links for FuenzalidaiteHide

Localities for FuenzalidaiteHide

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.

Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for 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 (eg from pseudomorphs.)

All localities listed without proper references should be considered as questionable.
Chile (TL)
  • Antofagasta
    • Antofagasta Province
      • Canchas
NM 90-94 (1997)
    • Tocopilla Province
      • María Elena
        • Pedro de Valdivia
Pueyo, J. J., Chong, G. & Vega, M. (1998): Mineralogy and parental brine evolution in the Pedro de Valdivia nitrate deposit, Antofagasta, Chile. Revista Geologica de Chile 25, 3-15. (in Spanish) ; Marta, V. E. G. A., & Pueyo, J. (1996) Parental Brine Evolution in the Chilean Nitrate Deposits (Pedro de Valdivia, II Region de Antofagasta). Mineralogical and Petrographic Data. Third ISAG, S1 Malo (France), 17-19/9/1996
  • Tarapacá
    • Tamarugal Province
      • Pozo Almonte
collected by Reynaldo Contreira
Personally collected by Reynaldo Contreira in 2006
Mineral and/or Locality  
Mindat Discussions Facebook Logo Instagram Logo Discord Logo is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © and the Hudson Institute of Mineralogy 1993-2021, except where stated. Most political location boundaries are © OpenStreetMap contributors. relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us - Report a bug/vulnerability Current server date and time: January 20, 2021 12:31:18 Page generated: December 24, 2020 02:29:37
Go to top of page