Learning Center What is a mineral?The most common minerals on earth Information for Educators Mindat Articles The Elements The Rock H. Currier Digital Library Geologic Time

Minerals by Properties Minerals by Chemistry Advanced Locality Search Random Mineral Random Locality Search by minID Localities Near Me Search Articles Search Glossary More Search Options

The Mindat Manual Add a New Photo Rate Photos Locality Edit Report Coordinate Completion Report Add Glossary Item

Mining Companies Statistics Users Mineral Museums Clubs & Organizations Mineral Shows & Events The Mindat Directory Device Settings The Mineral Quiz

Photo Search Photo Galleries Search by Color New Photos Today New Photos Yesterday Members' Photo Galleries Past Photo of the Day Gallery Photography

Mountainite

A valid IMA mineral species - grandfathered

This page is currently not sponsored. Click here to sponsor this page.

Photos of Mountainite (13)

Mountainite Gallery Search Photos of Mountainite

Edit Add Synonym Edit CIF structures Clear Cache

Mountainite

Bultfontein Mine, KEM JV Mine, Kimberley, Sol Plaatje Local Municipality, Frances Baard District Municipality, Northern Cape, South Africa

Mountainite

Yubileinaya pegmatite, Karnasurt Mountain, Lovozersky District, Murmansk Oblast, Russia

Mountainite

Yubileinaya pegmatite, Karnasurt Mountain, Lovozersky District, Murmansk Oblast, Russia

Mountainite

Bultfontein Mine, KEM JV Mine, Kimberley, Sol Plaatje Local Municipality, Frances Baard District Municipality, Northern Cape, South Africa

Mountainite

Yubileinaya pegmatite, Karnasurt Mountain, Lovozersky District, Murmansk Oblast, Russia

Mountainite

Yubileinaya pegmatite, Karnasurt Mountain, Lovozersky District, Murmansk Oblast, Russia

Mountainite

Bultfontein Mine, KEM JV Mine, Kimberley, Sol Plaatje Local Municipality, Frances Baard District Municipality, Northern Cape, South Africa

Mountainite

Yubileinaya pegmatite, Karnasurt Mountain, Lovozersky District, Murmansk Oblast, Russia

Hide all sections | Show all sections

About MountainiteHide

Edgar Donald Mountain

Formula:

KNa₂Ca₂[Si₈O₁₉(OH)] · 6H₂O

Colour:

white

Hardness:

Specific Gravity:

2.36

Crystal System:

Monoclinic

Name:

Named by J.A. Gard, H.F.W. Taylor, and R.A. Chalmers in 1957 for Edgar Donald Mountain (2 April 1901 – 30 April 1985), Professor of Geology, Rhodes University, Grahamstown, South Africa, who provided the first specimens for investigation.

Type Locality:

ⓘ Bultfontein Mine, KEM JV Mine (Kimberley Ekapa Mining Joint Venture mine; Kimberley Underground mine), Kimberley, Sol Plaatje Local Municipality, Frances Baard District Municipality, Northern Cape, South Africa

Closely related to cryptophyllite and shlykovite.

Unique IdentifiersHide

Mindat ID:

2795

Long-form identifier:

mindat:1:1:2795:9

GUID
(UUID V4):

614e9d53-45b1-466c-bece-b440d9a99ee6

IMA Classification of MountainiteHide

IMA status:

Approved, 'Grandfathered' (first described prior to 1959)

First published:

1957

Type description reference:

Gard, J. A., Taylor, H. F. W., Chalmers, R. A. (1957) An investigation of two new minerals: rhodesite and mountainite. Mineralogical Magazine and Journal of the Mineralogical Society, 31 (239). 611-623 doi:10.1180/minmag.1957.31.239.02

Classification of MountainiteHide

Strunz-mindat (2024):

9.GG.10

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

Dana 8th ed.:

77.2.3.1

77 : TECTOSILICATES Zeolites
2 : Zeolite group - related species

Hey's CIM Ref.:

14.6.6

14 : Silicates not Containing Aluminum
6 : Silicates of Ca with alkali or Mg or both

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

Symbol	Source	Reference
Mtn	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 MountainiteHide

Transparency:

Transparent, Translucent

Colour:

white

Streak:

white

Hardness:

3 on Mohs scale

Cleavage:

Poor/Indistinct
one doubtful in prism zone.

Density:

2.36 g/cm³ (Measured) 2.47 g/cm³ (Calculated)

Optical Data of MountainiteHide

Type:

Biaxial (+)

RI values:

n_α = 1.500 - 1.504 n_β = 1.505 - 1.510 n_γ = 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

Chemistry of MountainiteHide

Mindat Formula:

KNa₂Ca₂[Si₈O₁₉(OH)] · 6H₂O

Elements listed:

Ca, H, K, Na, O, Si - search for minerals with similar chemistry

Common Impurities:

Al,Mg,C

Crystallography of MountainiteHide

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 V:

1192.7 Å³

Morphology:

As matted laths and fibers, elongated along [010], forming small rosettes, to 2 mm.

Crystal StructureHide

Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4

View
CIF File Best | x | y | z | a | b | c

Rotation
Stop | Start

Labels
Console Off | On | Grey | Yellow

Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure

ID	Species	Reference	Link	Year	Locality	Pressure (GPa)	Temp (K)
0011131	Mountainite	Zubkova N V, Pekov I V, Pushcharovsky D Y, Chukanov N V (2009) The crystal structure and refined formula of mountainite, KNa2Ca2[Si8O19(OH)]6H2O* Zeitschrift fur Kristallographie 224 389-396		2009	Yubileinaya pegmatite, Lovozero alkaline complex, Kola Peninsula, Russia	0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Mountainite'
loop_
_publ_author_name
'Zubkova N V'
'Pekov I V'
'Pushcharovsky D Y'
'Chukanov N V'
_journal_name_full 'Zeitschrift fur Kristallographie'
_journal_volume 224 
_journal_year 2009
_journal_page_first 389
_journal_page_last 396
_publ_section_title
;
 The crystal structure and refined formula of mountainite, KNa2Ca2[Si8O19(OH)]*6H2O
;
_database_code_amcsd 0011131
_chemical_compound_source 'Yubileinaya pegmatite, Lovozero alkaline complex, Kola Peninsula, Russia'
_chemical_formula_sum 'K Na2 Ca2 Si8 O26 H13'
_cell_length_a 13.704
_cell_length_b 6.5760
_cell_length_c 13.751
_cell_angle_alpha 90
_cell_angle_beta 105.752
_cell_angle_gamma 90
_cell_volume 1192.668
_exptl_crystal_density_diffrn      2.281
_symmetry_space_group_name_H-M 'P 1 2/c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,-y,1/2+z'
  '-x,y,1/2-z'
  '-x,-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
K   0.00000   0.27580   0.25000   1.00000   0.02920
Na1   0.45000   0.84660   0.58170   0.50000   0.04300
Na2   0.43170   0.70750   0.44120   0.50000   0.03000
Ca   0.01912   0.24440   0.56031   1.00000   0.01290
Si1   0.33509   0.22350   0.64951   1.00000   0.01170
Si2   0.21930   0.46900   0.76350   1.00000   0.01090
Si3   0.20420   0.16380   0.12840   1.00000   0.01180
Si4   0.20960   0.50420   0.98330   1.00000   0.01200
O1   0.79580   0.29400   0.26960   1.00000   0.02200
O2   0.11920   0.34370   0.71390   1.00000   0.01800
O3   0.31960   0.38180   0.73490   1.00000   0.01800
O4   0.90340   0.07680   0.42650   1.00000   0.02250
O5   0.27240   0.29750   0.53830   1.00000   0.02000
O6   0.25430   0.47030   0.88600   1.00000   0.01600
O7   0.74950   0.30640   0.44410   1.00000   0.01700
O8   0.29300   0.00550   0.67340   1.00000   0.02100
O9   0.45340   0.20510   0.65830   0.50000   0.02200
O-H9   0.45340   0.20510   0.65830   0.50000   0.02200
O10   0.09090   0.46340   0.46030   1.00000   0.01800
Wat11   0.90940   0.08370   0.65120   1.00000   0.02300
Wat12   0.50000   0.68500   0.75000   1.00000   0.07500
Wat13   0.47470   0.57300   0.46910   0.50000   0.03800
Wat14   0.36000   0.05000   0.39730   0.50000   0.04200
Wat15   0.54880   0.93800   0.56800   0.50000   0.05500

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
2.94 Å	(vvs)
6.6 Å	(vs)
13.1 Å	(s)
4.67 Å	(s)
2.80 Å	(ms)
1.967 Å	(ms)
4.18 Å	(m)

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Stage 3a: Earth’s earliest Hadean crust	>4.50
7 : Ultramafic igneous rocks
Stage 4b: Highly evolved igneous rocks	>3.0
35 : Ultra-alkali and agpaitic igneous rocks

Type Occurrence of MountainiteHide

Type Locality:

General Appearance of Type Material:

silky white fibers

Place of Conservation of Type Material:

The Natural History Museum, London, England, 1957,369; National Museum of Natural History, Washington, D.C., USA, 114792.

Geological Setting of Type Material:

Kimberlite pipe

Associated Minerals at Type Locality:

Rhodesite

Reference:

Gard, J.A., Taylor, H.F.W., Chalmers, R.A. (1957) An investigation of two new minerals: rhodesite and mountainite. Mineralogical Magazine: 31: 611-62

Download:

https://rruff.info/rruff_1.0/uploads/MM31_611.pdf

Other Language Names for MountainiteHide

German:Mountainit

Spanish:Mountainita

Common AssociatesHide

Associated Minerals Based on Photo Data:

7 photos of Mountainite associated with Raite	Mn²⁺Mn²⁺₂Na₂(◻_1.75Ti_0.25)Si₈O₂₀(OH)₂(H₂O)₄ · Na(H₂O)₆
5 photos of Mountainite associated with Vitusite-(Ce)	Na₃(Ce,La,Nd)(PO₄)₂
4 photos of Mountainite associated with Steenstrupine-(Ce)	Na₁₄Mn²⁺₂Fe³⁺₂Ce₆Zr(Si₆O₁₈)₂(PO₄)₆(PO₃OH)(OH)₂ · 2H₂O
4 photos of Mountainite associated with Natrolite	Na₂Al₂Si₃O₁₀ · 2H₂O
3 photos of Mountainite associated with Magnesio-arfvedsonite	{Na}{Na₂}{Mg₄Fe³⁺}(Si₈O₂₂)(OH)₂
2 photos of Mountainite associated with Sazhinite-(Ce)	Na₂CeSi₆O₁₄ · 6H₂O
1 photo of Mountainite associated with Aegirine	NaFe³⁺Si₂O₆
1 photo of Mountainite associated with Zorite	Na₈(Ti,Nb)₅(Si₆O₁₇)₂(OH,O)₅ · 14H₂O
1 photo of Mountainite associated with Leucosphenite	BaNa₄Ti₂B₂Si₁₀O₃₀

Related Minerals - Strunz-mindat Grouping Hide

9.GG.05

Cowlesite

CaAl₂Si₃O₁₀ · 6H₂O

Orth. mmm (2/m 2/m 2/m)

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.

Internet Links for MountainiteHide

mindat.org URL:

https://www.mindat.org/min-2795.html
Please feel free to link to this page.

Search Engines:

Look for Mountainite on Google

Look for Mountainite images on Google

Look for Mountainite on Bing

Look for Mountainite images on Bing

Look for Mountainite on DuckDuckGo

Look for Mountainite images on DuckDuckGo

Look for Mountainite in the Rock H. Currier Digital Library

External Links:

Look for Mountainite on Webmineral

Look for Mountainite on Wikipedia

Look for Mountainite on Mineralien Atlas

Raman and XRD data at RRUFF project

References and PDF downloads at RRUFF project

American Mineralogist Crystal Structure Database

Handbook of Mineralogy page PDF

Mineral Dealers:

Buy from David K Joyce minerals

Wilensky Exquisite Minerals

Buy from McDougall Minerals

High-end worldwide specimens & outstanding customer service

Blue Gems Australian & International

Buy rare minerals from Excalibur Minerals

The Arkenstone - Fine Minerals

References for MountainiteHide

Reference List:

Fleischer, M. (1958) New mineral names. American Mineralogist: 43: 623-626.

Bussen, I.V., Latysheva, L.G., Men'shikov, Y.P., Mer'kov, A.N., Romanova, T.S., Sakharov, A.S. (1973) First find of mountainite in the Soviet Union. Doklady Akademii Nauk SSSR: 210: 674-677. (in Russian)

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

Askerov, R.G., Chiragov, M.I., Ragimov, K.G., Shirinova, A.F. (2009) About Crystal Structure of Mountainite. Acta Crystallographica A: 65: 255-255.

(2023) Mountainite. Handbook of Mineralogy. Mineralogical Society of America

Localities for MountainiteHide

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 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). ~~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 (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.


Germany
Baden-Württemberg Freiburg Region Tuttlingen Immendingen ⓘ Höwenegg Quarry (Hewenegg Quarry)	Tschernich (1992)

Romania
Hunedoara County ⓘ Cornet Hill	Pascal et al. (2001)

Russia
Murmansk Oblast Lovozersky District Karnasurt Mountain ⓘ Yubileinaya pegmatite	Pluth et al. (1997) +2 other references

South Africa (TL)
Northern Cape Frances Baard District Municipality Sol Plaatje Local Municipality Kimberley KEM JV Mine (Kimberley Ekapa Mining Joint Venture mine; Kimberley Underground mine) ⓘ Bultfontein Mine (TL)	Gard et al. (1957)

USA
California Trinity County Klamath Mountains Trinity Mountains Halls Gulch Mining District Wildcat Peak ⓘ Trinity Mining claim	Van Nostrand Reinholt Press: 442 +3 other references

Mountainite

About MountainiteHide

Unique IdentifiersHide

IMA Classification of MountainiteHide

Classification of MountainiteHide

Mineral SymbolsHide

Physical Properties of MountainiteHide

Optical Data of MountainiteHide

Chemistry of MountainiteHide

Crystallography of MountainiteHide

Crystal StructureHide

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Type Occurrence of MountainiteHide

Other Language Names for MountainiteHide

Common AssociatesHide

Related Minerals - Strunz-mindat GroupingHide

Other InformationHide

Internet Links for MountainiteHide

References for MountainiteHide

Localities for MountainiteHide

Locality ListHide

Related Minerals - Strunz-mindat Grouping Hide