Help mindat.org|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on MindatThe Mindat Store
Minerals by PropertiesMinerals by ChemistryRandom MineralSearch by minIDLocalities Near MeSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportAdd Glossary Item
StatisticsMember ListBooks & MagazinesMineral Shows & EventsThe Mindat DirectoryHow to Link to MindatDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Mountainite

This page is currently not sponsored. Click here to sponsor this page.
Formula:
KNa2Ca2[Si8O19(OH)] · 6H2O
System:
Monoclinic
Colour:
white
Hardness:
3
Name:
For Edgar Donald Mountain, Rhodes University, Grahamstown.
Closely related to cryptophyllite and shlykovite.

Classification of Mountainite

Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
9.GG.10

9 : SILICATES (Germanates)
G : Tektosilicates with zeolitic H2O; zeolite family
G : Unclassified zeolites
77.2.3.1

77 : TECTOSILICATES Zeolites
2 : Zeolite group - related species
14.6.6

14 : Silicates not Containing Aluminum
6 : Silicates of Ca with alkali or Mg or both
mindat.org URL:
http://www.mindat.org/min-2795.html
Please feel free to link to this page.

First Recorded Occurrence of Mountainite

General Appearance of First Recorded Material:
silky white fibers
Year of Discovery:
1957
Geological Setting of First Recorded Material:
Kimberlite pipe
Associated Minerals at First Recorded Locality:

Physical Properties of Mountainite

Colour:
white
Streak:
white
Hardness (Mohs):
3

Crystallography of Mountainite

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P2/b
Cell Parameters:
a = 13.704(2) Å, b = 6.5760(10) Å, c = 13.751(2) Å
β = 105.752(10)°
Ratio:
a:b:c = 2.084 : 1 : 2.091
Unit Cell Volume:
V 1192.7 ų
Z:
2

Optical Data of Mountainite

Type:
Biaxial (+)
RI values:
nα = 1.500 - 1.504 nβ = 1.505 - 1.510 nγ = 1.513 - 1.519
2V:
Calculated: 78° to 80°
Max Birefringence:
δ = 0.013 - 0.015
Image shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:
Low
Dispersion:
relatively strong

Chemical Properties of Mountainite

Formula:
KNa2Ca2[Si8O19(OH)] · 6H2O
Essential elements:
All elements listed in formula:
Common Impurities:
Al,Mg,C

Relationship of Mountainite to other Species

14.6.1CombeiteNa2Ca2(Si6O18)0.5
14.6.2PectoliteNaCa2(HSi3O9)
14.6.3Pectolite-M2abcNaCa2[HSi3O9]
14.6.4DenisoviteCa2(K,Na)Si3O8(F,OH)2
14.6.5TokkoiteK2Ca4Si7O17(O,OH,F)4
14.6.7RhodesiteKHCa2Si8O19 · 5H2O
14.6.8MiseriteK(Ca,Ce)4Si5O13(OH)3
14.6.9ÅkermaniteCa2Mg(Si2O7)
14.6.10MonticelliteCaMgSiO4
14.6.11MerwiniteCa3Mg(SiO4)2
14.6.12DiopsideCaMgSi2O6
14.6.13Tremolite☐{Ca2}{Mg5}(Si8O22)(OH)2

Other Names for Mountainite

Name in Other Languages:
German:Mountainit
Spanish:Mountainita

Other Information

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 Mountainite

Reference List:
American Mineralogist (1958): 43: 624.

Doklady Akademii Nauk SSSR (1973): 210: 676.

Zubkova, N.V., I.V. Pekov, D.Yu. Pushcharovsky, N.V. Chukanov (2009): The crystal structure and refined formula of mountainite. Zeitschrift für Kristallographie 224, 389-396.

Internet Links for Mountainite

Localities for Mountainite

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.
(TL) indicates type locality for a valid mineral species. (FRL) indicates first recorded locality for everything else. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
Germany
 
  • Baden-Württemberg
    • Hegau
      • Immendingen
Tschernich, R. (1992), Zeolites of the World, p.42
Romania
 
  • Hunedoara Co.
    • Hunedoara
The Canadian Mineralogist Vol. 39, pp. 1405-1434 (2001)
Russia
 
  • Northern Region
    • Murmanskaja Oblast'
      • Kola Peninsula
        • Lovozero Massif
          • Karnasurt Mt
Pekov, I. (1998) Minerals First discovered on the territory of the former Soviet Union 369p. Ocean Pictures, Moscow; Zubkova, N. V., Pekov, I. V., Pushcharovsky, D. Y., & Chukanov, N. V. (2009). The crystal structure and refined formula of mountainite, KNa2Ca2 [Si8O19 (OH)]⊙ 6 H2O. Zeitschrift für Kristallographie, 224(8), 389-396.; Pluth, J. J., Smith, J. V., Pushcharovsky, D. Y., Semenov, E. I., Bram, A., Riekel, C., ... & Broach, R. W. (1997). Third-generation synchrotron x-ray diffraction of 6-μm crystal of raite,≈ Na3Mn3Ti0. 25Si8O20 (OH) 2⋅ 10H2O, opens up new chemistry and physics of low-temperature minerals. Proceedings of the National Academy of Sciences, 94(23), 12263-12267.
South Africa
 
  • Free State Province
    • Lejweleputswa District
Min.Mag.(1957) 31, 611-623; Minerals of South Africa
USA
 
  • California
    • Trinity Co.
      • Klamath Mts
        • Trinity Mts
          • Halls Gulch District
            • Wildcat Peak
Barnes, I., J.B. Rapp & J.R. O’Neil (1972), Metamorphic assemblages and the direction of flow of metamorphic fluids in four instances of serpentinization: Contributions to Mineralogy and Petrology: 35: 264; Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 442; www.mineralsocal.org.
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 1993-2015, 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: March 29, 2015 05:33:02 Page generated: March 28, 2015 20:45:01