ALMOST THERE!. Help us with a final push needed to keep mindat.org running. Click here to help.
Catawiki are hosting a mindat.org benefit auction. All proceeds to mindat.org! BID NOW
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 Articles
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsThe ElementsUsersBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Lecontite

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

About LecontiteHide

John Lawrence LeConte
Formula:
(NH4,K)NaSO4 · 2H2O
Colour:
Colourless; colourless in transmitted light
Lustre:
Vitreous
Hardness:
2 - 2½
Specific Gravity:
1.745
Crystal System:
Orthorhombic
Name:
After John L. LeConte (1825-1883), American entomologist, discoverer of the species.
This page provides mineralogical data about Lecontite.


Classification of LecontiteHide

Approved, 'Grandfathered' (first described prior to 1959)
7.CD.15

7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
C : Sulfates (selenates, etc.) without additional anions, with H2O
D : With only large cations
29.2.1.1

29 : HYDRATED ACID AND NORMAL SULFATES
2 : A2XO4·xH2O

Physical Properties of LecontiteHide

Vitreous
Transparency:
Transparent
Colour:
Colourless; colourless in transmitted light
Hardness:
2 - 2½ on Mohs scale
Density:
1.745 g/cm3 (Measured)    1.747 g/cm3 (Calculated)
Comment:
Synthetic

Optical Data of LecontiteHide

Type:
Biaxial (-)
RI values:
nα = 1.440 nβ = 1.454 nγ = 1.455
2V:
Measured: 40° to 43°, Calculated: 28°
Max Birefringence:
δ = 0.015
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
Surface Relief:
Moderate
Dispersion:
dispersion not observed

Chemical Properties of LecontiteHide

Formula:
(NH4,K)NaSO4 · 2H2O
IMA Formula:
(NH4)Na(SO4) · 2H2O

Crystallography of LecontiteHide

Crystal System:
Orthorhombic
Class (H-M):
2 2 2 - Disphenoidal
Space Group:
P21 21 21
Cell Parameters:
a = 8.216(8) Å, b = 12.854(1) Å, c = 6.232(8) Å
Ratio:
a:b:c = 0.639 : 1 : 0.485
Unit Cell V:
658.15 ų (Calculated from Unit Cell)
Z:
4
Morphology:
Thin prismatic crystals; also very short and wide, very fine grained masses.

Type Occurrence of LecontiteHide

Place of Conservation of Type Material:
Yale University
Geological Setting of Type Material:
Cave

Other Language Names for LecontiteHide

German:Lecontit
Spanish:Lecontita

Common AssociatesHide

Mascagnite(NH4)2SO4
ThénarditeNa2SO4

Related Minerals - Nickel-Strunz GroupingHide

7.CD.Campostriniite(Bi3+,Na)3(NH4,K)2Na2(SO4)6·H2OMon. 2/m : B2/b
7.CD.05MatteucciteNaHSO4 · H2OMon.
7.CD.10MirabiliteNa2SO4 · 10H2OMon. 2/m
7.CD.20HydroglauberiteNa10Ca3(SO4)8 · 6H2OMon.
7.CD.25EugsteriteNa4Ca(SO4)3 · 2H2OMon.
7.CD.30GörgeyiteK2Ca5(SO4)6 · H2OMon.
7.CD.35Koktaite(NH4)2Ca(SO4)2 · H2OMon.
7.CD.35SyngeniteK2Ca(SO4)2 · H2OMon. 2/m : P21/m
7.CD.40GypsumCaSO4 · 2H2OMon. 2/m
7.CD.45BassaniteCaSO4 · 0.5H2OMon. 2 : B2
7.CD.50Zircosulfate(Zr,Ti)(SO4)2 · 4H2OOrth.
7.CD.55SchieffelinitePb10Te6+6O20(OH)14(SO4)(H2O)5Orth. mmm (2/m 2/m 2/m) : Cmcm
7.CD.60MontaniteBi2(TeO6) · 2H2O
7.CD.65OmongwaiteNa2Ca5(SO4)6 · 3H2OMon. 2 : B2

Other InformationHide

Notes:
Taste bitter, salty
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 LecontiteHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Taylor (1858) American Journal of Science: 26: 273.
Dawson (1918) Journal of the Chemical Society of London: 113: 675.
Larsen, E.S. (1921) The Microscopic Determination of the Nonopaque Minerals, First edition, USGS Bulletin 679: 99.
Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II. John Wiley and Sons, Inc., New York, 7th edition, revised and enlarged: 438-439.
American Mineralogist (1963): 48: 180.
Acta Crystallographica (1967): 22: 683-687.

Internet Links for LecontiteHide

Localities for LecontiteHide

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
 
  • Antofagasta
    • Antofagasta Province
      • Mejillones
        • Mejillones peninsula
https://e-rocks.com/blogs/1/chilean-blues-update-find-coronel-manuel-rodriguez-mine
    • El Loa Province
      • Calama
        • Chuquicamata District
James A. Bauer Collection
France
 
  • Hauts-de-France
    • Pas-de-Calais
Naze-Nancy Masalehdani, M., Mees, F., Dubois, M., Coquinot, Y., Potdevin, J.-L., Fialin, M. & Blanc-Valleron, M.-M. (2009): Condensate minerals from a burning coal-waste heap in Avion, Northern France. Can. Mineral. 47, 573-591.
Honduras (TL)
 
  • La Paz Department
Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 439; American Mineralogist (1963): 48: 180; J.W. Anthony, R.A. Bideaux, K.W. Bladh, M.C. Nichols: Handbook of Mineralogy, Vol. V (2003)
Sweden
 
  • Stockholm
    • Stockholm
Jalilehvand, F., Sandstrom, M., Persson, I., Gelius, U., & Frank, P. (2001). Acidity and Salt Precipitation on the Vasa; The Sulfur Problem. Proceedings 8th ICOM-CC WO AM Conference Stockholm 11-15 June 2001
USA
 
  • California
    • Imperial Co.
      • Salton Sea
        • Mullet Island
Adams, P., & Lynch, D. (2014). A mineralogical inventory of geothermal features southeast of the Salton Sea, Imperial County, California. Trough to trough: The Colorado River and the Salton Sea (Reynolds, R, 39-43.
Adams, P., & Lynch, D. (2014). A mineralogical inventory of geothermal features southeast of the Salton Sea, Imperial County, California. Trough to trough: The Colorado River and the Salton Sea (Reynolds, R, 39-43.
  • Nevada
    • Washoe Co.
NBMG Spec. Pub. 31 Minerals of Nevada
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2018, except where stated. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: December 16, 2018 08:01:34 Page generated: December 15, 2018 23:46:46
Go to top of page