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About EucryptiteHide

Colorless, white, pale tan, pale gray.
Sub-Vitreous, Resinous, Greasy
Specific Gravity:
2.657 - 2.666
Crystal System:
Member of:
Named in 1880 by Brush and Dana from the Greek for "well concealed", in allusion to its occurrence embedded in albite. Also known as α-eucryptite or alpha-eucryptite.

Classification of EucryptiteHide

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

9 : SILICATES (Germanates)
A : Nesosilicates
A : Nesosilicates without additional anions; cations in tetrahedral [4] coordination
Dana 7th ed.:

51 : NESOSILICATES Insular SiO4 Groups Only
1 : Insular SiO4 Groups Only with cations in [4] coordination

16 : Silicates Containing Aluminum and other Metals
1 : Aluminosilicates of Li

Physical Properties of EucryptiteHide

Sub-Vitreous, Resinous, Greasy
Transparent, Translucent
Usually sub-vitrous
Colorless, white, pale tan, pale gray.
6½ on Mohs scale
Poor on {101¯0} and {0001}.
Irregular/Uneven, Conchoidal
Pure masses from Bikita show conchoidal fracture.
2.657 - 2.666 g/cm3 (Measured)    2.654 g/cm3 (Calculated)

Optical Data of EucryptiteHide

Uniaxial (+)
RI values:
nω = 1.570 - 1.573 nε = 1.583 - 1.587
Max Birefringence:
δ = 0.013
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
Surface Relief:

Chemical Properties of EucryptiteHide

Common Impurities:

Crystallography of EucryptiteHide

Crystal System:
Class (H-M):
3 - Rhombohedral
Space Group:
Cell Parameters:
a = 13.48 Å, c = 9.01 Å
a:c = 1 : 0.668
Unit Cell V:
1,417.87 ų (Calculated from Unit Cell)
Usually massive, rarely in equant euhedral crystals with {101¯0}, {0001}, and {112¯0}. (Bikita: Hurlbut, 1962). More complec crystals found at Kings Mountain, North Carolina, USA.

X-Ray Powder DiffractionHide

Image Loading

Radiation - Copper Kα
Data Set:
Data courtesy of RRUFF project at University of Arizona, used with permission.
Powder Diffraction Data:
6.74 (60)
4.20 (30)
3.96 (100)
3.89 (40)
3.37 (90)
2.74 (80)
2.55 (60)
2.38 (30)

Type Occurrence of EucryptiteHide

Synonyms of EucryptiteHide

Other Language Names for EucryptiteHide

Simplified Chinese:锂霞石

Relationship of Eucryptite to other SpeciesHide

Member of:
Other Members of this group:
PhenakiteBe2SiO4Trig. 3 : R3
WillemiteZn2SiO4Trig. 3 : R3

Common AssociatesHide

LepidoliteA Li-rich mica in, or close to, the so-called Polylithionite-Trilithionite series.
Associated Minerals Based on Photo Data:
Spodumene10 photos of Eucryptite associated with Spodumene on mindat.org.
Cookeite5 photos of Eucryptite associated with Cookeite on mindat.org.
Lepidolite4 photos of Eucryptite associated with Lepidolite on mindat.org.
Quartz4 photos of Eucryptite associated with Quartz on mindat.org.
Cymatolite3 photos of Eucryptite associated with Cymatolite on mindat.org.
Kunzite2 photos of Eucryptite associated with Kunzite on mindat.org.

Related Minerals - Nickel-Strunz GroupingHide

9.AA.05PhenakiteBe2SiO4Trig. 3 : R3
9.AA.05WillemiteZn2SiO4Trig. 3 : R3
9.AA.10LiberiteLi2BeSiO4Mon. m : Pm

Related Minerals - Dana Grouping (8th Ed.)Hide 3 : R3 3 : R3

Related Minerals - Hey's Chemical Index of Minerals GroupingHide

16.1.1PetaliteLiAl(Si4O10)Mon. 2/m : P2/b
16.1.4VirgiliteLiAlSi2O6Hex. 6 2 2 : P62 2 2
16.1.5Cookeite(Al2Li)Al2(AlSi3O10)(OH)8Mon. 2/m
16.1.6BikitaiteLiAlSi2O6 · H2OTric. 1 : P1
16.1.8SwineforditeLi(Al,Li,Mg)4((Si,Al)4O10)2(OH,F)4 · nH2OMon.
16.1.13Clino-holmquistite Root Name☐{Li2}{Z2+3Z3+2}(Si8O22)(OH,F,Cl)2Mon.
16.1.15BityiteLiCaAl2(AlBeSi2O10)(OH)2Mon. 2/m : B2/b
16.1.16SogdianiteK(□,Na)2Li3(Zr,Fe,Ti)2[Si12O30]Hex. 6/mmm (6/m 2/m 2/m) : P6/mcc

Fluorescence of EucryptiteHide

Magenta-red or orange under SW UV.

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 EucryptiteHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Dana, E.S. (1892) Dana's System of Mineralogy, 6th. edition: 426.
Mrose, M., E., 1953, α-Eucryptite Problem [abstract], American Mineralogist, v. 38. p. 353.
Hurlbut, C.S., Jr. (1962) Eucryptite from Bikita, Southern Rhodesia. American Mineralogist: 47: 557-559.
Leavens, P.B., Hurlbut, C.S., Jr., and Nelen, J.A. (1968) Eucryptite and bikitaite from King's Mountain, North Carolina. American Mineralogist: 53: 1202-1207.
Černý, P. (1972) The Tanco pegmatite at Bernic Lake, Manitoba. VII. Eucryptite. Canadian Mineralogist: 11: 708-713.
Lahti, S.I., Kallio, P., von Knorring, O. (1982): The composition, physical properties and occurrence of eucryptite from the Haapaluoma pegmatite, Finland. Bull.Geol.Soc.Finland, 54, 1-2; 5-13.
Hesse, K.-F. (1985) Crystal structures of natural and synthetic α-eucryptite, LiAlSiO4. Zeitschrift für Kristallographie: 172: 147-151.
Anthony, Bideaux, Bladh & Nichols (1995), Handbook of Mineralogy, Vol. II.
Gaines, Richard V., H. Catherine, W. Skinner, Eugene E. Foord, Brian Mason, Abraham Rosenzweig, Vandall T. King (1997), Dana's New Mineralogy : The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana.
Zeitschrift für Kristallographie: 172: 147-151.

Internet Links for EucryptiteHide

Localities for EucryptiteHide

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.
  • Western Australia
    • Coolgardie Shire
      • Nepean
Calderwood, M.A., Grguric, B.A., Jacobson, M.I. (2007) Guidebook to the Pegmatites of Western Australia. Hesperian Press, Carlisle, Western Australia, 394 pages.
  • Manitoba
    • Lac-du-Bonnet area
      • Bernic Lake
Canadian Mineralogist Vol. 15, pp.489-499 (1977); Canadian Mineralogist Vol. 11,pp.591-608 (1972); Bannatyne, B. B. (1985). Industrial minerals in rare-element pegmatites of Manitoba (Vol. 84, No. 1). Manitoba Energy and Mines, Geological Services.
  • Ontario
    • Kenora District
      • Paterson Lake Area
Blackburn C. et al (2002) Separation Rapids Rare-Element Pegmatite Field, Ontario. in 48th Annual Meeting Institute on Lake Superior Geology. Vol 48 Part 2 - Field Trip Guidebook
Tindle, A.G., Breaks, F.W., and Selway, J.B. (2002) Tourmaline in petalite-subtype gramitic pegmatites: evidence of fractionation and contamination from Pakeagama Lake and Separation Lake areas of northwestern Ontario, Canada. Canadian Mineralogist, 40, 753-788.
  • Hunan
    • Chenzhou
      • Linwu Co.
        • Xianghualing Sn-polymetallic ore field
Anthony, J.W. et al.: Handbook of Mineralogy
  • Jiangxi
    • Yichun
      • Yuanzhou District
        • Yichun complex (Yashan batholith)
Xudong Che, Rucheng Wang, Huan Hu, Wenlan Zhang, and Xiaolong Huang (2007): Acta Petrologica Sinica 23(6), 1552-1560
  • Xinjiang
    • Yili Hasake Autonomous Prefecture (Ili Kazakh Autonomous Prefecture)
      • Aletai Prefecture (Altay Prefecture)
        • Fuyun Co. (Koktokay Co.)
          • Koktokay pegmatite field (Keketuohai pegmatite field)
            • Altay Mine
Tianren Zou, Xiangchen Zhang, Fuyi Jia, Rucong Wang, Huizhi Cao, and Boqing Wu (1986): Mineral Deposits 5(4), 34-48; Liangming Fan, Yuyuan Mao, Yongwen Wan, and Shiwei Luan (1994): Journal of Mineralogy and Petrology 15(1); Huanzhang Lu, Zhonggang Wang, and Yuansheng Li (1997): Chinese Journal of Geochemistry 16(1), 43-52
  • Red Sea
    • Eastern Desert
Gehad M. Saleh (2007) Rare-Metal Pegmatites from the Southeastern Desert, Egypt: Geology, Geochemistry, and Petrogenesis. International Geology Review Vol. 49:824-843.
  • South Ostrobothnia
    • Kuortane
Lahti, Seppo I. 1998A. Kaatialan pegmatiitista ja sen mineraaleista. Kivi-lehti 2, 6–26; Makitie, H., Karkkainen, N., Lahti, S. I., & Alviola, R. (2001). Compositional variation of granitic pegmatites in relation to regional metamorphism in the Seinajoki region, western Finland. Special Paper 30 - Geological Survey of Finland, 31-59.
    • Seinäjoki
      • Peräseinäjoki
Lahti, S. I., Kallio, P. and von Knorring, O. (1982): The composition, physical properties and occurrence of eucryptite from the Haapaluoma pegmatite, Finland. Bull.Geol. Soc. Finland 54, 1-2, 5-13.
  • Erongo Region
    • Arandis
      • Cape Cross area
Keller, P. (1991) The occurrence of Li-Fe-Mn phosphate minerals in granitic pegmatites of Namibia. Communications of the Geological Survey of Namibia, 7, 21-35.
  • Karas Region
    • Karasburg District
      • Tantalite Valley
Baldwin, J. R. (1994). Lithium and tantalum mineralization in rare-element pegmatites from southern Africa (Doctoral dissertation, University of St Andrews).
  • Vila Real
    • Barroso-Alvão pegmatite field
Novák, M. et al. (2009): Ferronigerite with dominant substitution TiSn-1 in muscovite+chlorite aggregate from massive quartz nodule associated with a petalite-rich aplite-pegmatite of the Barroso-Alvão pegmatite field, Northern Portugal. N. Jb. Mineral. Abh. 186, 67-78.
  • Irkutsk Oblast
P.M. Kartashov data; Evseev, A. A. (1973) Siberia's Crystals and Symmetry in the Distribution of Occurences of Minerals. World of Stone 1:11-20
  • Murmansk Oblast
    • Voron'i Tundry
James Cheshire collection
South Africa
  • Northern Cape
    • Namakwa District (Namaqualand)
Minerals of South Africa
      • Steinkopf
Minerals of South Africa
  • Castile and Leon
    • Salamanca
Roda-Robles, E., Vieira, R., Pesquera, A., & Lima, A. (2010). Chemical variations and significance of phosphates from the Fregeneda-Almendra pegmatite field, Central Iberian Zone (Spain and Portugal). Mineralogy and Petrology, 100(1-2), 23-34.
Encarnación Roda-Robles, Alfonso Pesquera (2007) Locality no. 3: Lepidolite-spodumene-rich and cassiterite-rich pegmatites from the Feli open-pit, (La Fregeneda, Salamanca, Spain) in ALEXANDRE LIMA & ENCARNACIÓN RODA ROBLES ed (2007) GRANITIC PEGMATITES: THE STATE OF THE ART - FIELD TRIP GUIDEBOOK. MEMÓRIAS N. º 9, UNIV. DO PORTO, FACULDADE DE CIÊNCIAS, DEPARTAMENTO DE GEOLOGIA pp 55-64
  • Stockholm
    • Haninge
      • Utö
Langhof, J., Jonson, E, Gustafsson, L. & Otter, B. (1998): Utö- en klassisk svensk mineralfyndort. Bergverksmuseets Skrift 14, 29-31
  • England
    • Devon
      • West Devon
        • Okehampton Hamlets
Fraudulent Kingsbury locality.
  • Arizona
    • Yavapai Co.
AmMin 67: 97-113 (1982)
        • Independence Gulch
Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 217; London, D. & D.M. Burt (1978), Lithium pegmatites of the White Picacho district, Maricopa and Yavapai Cos., AZ, in D.M. Burt and T.L. Péwé (editors), Guidebook to the geology of central Arizona, AZ Bur. Geol. Min. Tech. Spec. Paper 2: 61-72; London, D. & D.M. Burt (1982b), Lithium aluminosilicate occurrences in pegmatites and the aluminosilicate phase diagram, Am.Min.: 67: 483-509.
Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 217; London, D. & D.M. Burt (1978), Lithium pegmatites of the White Picacho district, Maricopa and Yavapai Cos., AZ, in D.M. Burt and T.L. Péwé (editors), Guidebook to the geology of central AZ, AZ Bur. Geol. Min. Tech. Spec. Paper 2: 61-72; London, D. & D.M. Burt (1982b), Lithium aluminosilicate occurrences in pegmatites and the aluminosilicate phase diagram, Am.Min.: 67: 483-509.
  • Connecticut
    • Fairfield Co.
      • Redding (Reading)
        • Branchville
Brush and Dana (1880); AmMin 31:329-345 (1946); USGS Prof Paper 255; Rocks & Minerals (1995) 70:396-409; Ronald Januzzi collection
    • Middlesex Co.
      • Portland
        • Collins Hill
          • Strickland pegmatite (Strickland-Cramer Quarry; Strickland-Cramer Mine; Strickland-Cramer Feldspar-Mica Quarries)
Schooner, Richard. (1958): The Mineralogy of the Portland-East Hampton-Middletown-Haddam Area in Connecticut (With a few notes on Glastonbury and Marlborough). Published by Richard Schooner; Ralph Lieser of Pappy’s Beryl Shop, East Hampton; and Howard Pate of Fluorescent House, Branford, Connecticut.; Schooner, Richard. (circa 1985), Untitled manuscript on central Connecticut mineralogy.
  • Maine
    • Oxford Co.
      • Newry
King, V. and Foord, E., 1994, Mineralogy of Maine, v. 1.
  • New Hampshire
    • Strafford Co.
      • Strafford
        • Parker Mountain
Rocks & Min.:64:504.; Rocks & Minerals 80:4 pp234-241
  • New Mexico
    • Taos Co.
      • Picuris District
Northrop, Minerals of New Mexico, 3rd Rev. Ed., 1996; Jahns, R. H. and Ewing, R. C. (1977): The Harding mine, Taos County, New Mexico. Mineralogical Record, 8 (2): 115-126.
  • North Carolina
    • Alexander Co.
London,David and Burt,Donald M.,(1982) Lithium Aluminosilicate Occurrences in Pegmatites and the Lithium Aluminosilicate Phase Diagram : American Mineralogist,Vol.67,pg.483-493,1982
    • Cleveland Co.
      • Kings Mountain District
Am Min 54 (1969), 1467-1469; Rocks and Minerals, (1985) 60:76-82; Carolina Geological Society Field Trip Guidebook 1981, 39-48
  • South Dakota
    • Custer Co.
      • Custer District
        • Fourmile
Rocks & Minerals: 75(3): 156-169.; Staatz, M. H.; Page, L. R.; Norton, J. J.; Wilmarth, V. R. (1963) Exploration for beryllium at the Helen Beryl, Elkhorn, and Tin Mountain pegmatites, Custer County, South Dakota. USGS Prof. Paper 297C.
    • Pennington Co.
      • Keystone District
        • Keystone
Rocks & Minerals: 67(6): 380-388.; U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
  • Masvingo
    • Bikita area
Zeolites of the World, Rudy W. Tschernich 1992; Cerny, P., Anderson, A. J., Tomascak, P. B., & Chapman, R. (2003). Geochemical and morphological features of beryl from the Bikita granitic pegmatite, Zimbabwe. The Canadian Mineralogist, 41(4), 1003-1011.
Amer.Min.(1958) 43, 768-770
Mineral and/or Locality  
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