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Halloysite-7Å

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Formula:
Al
 
2
(Si
 
2
O
 
5
)(OH)
 
4
System:Monoclinic
Name:
Named after the Belgian geologist Jean-Baptiste d'Omalius d'Halloy, (February 16th 1783 - January 15th 1875), who discovered the mineral. He was a nobleman, a statesman, and pioneer of modern geology in Belgium. The 7-Å(ngström) refers to the layer thickness.


Note: halloysite-7Å is NOT a polytype of halloysite.
It is an approved (grandfathered) species distinct from Halloysite-10Å.

A synonym is "metahalloysite."

See also the chemically identical kaolinite.



Classification of Halloysite-7Å

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Nickel-Strunz 10th (pending) edition ID:9.ED.10

9 : SILICATES (Germanates)
E : Phyllosilicates
D : Phyllosilicates with kaolinite layers composed of tetrahedral and octahedral nets
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Type Occurrence of Halloysite-7Å

Type Locality:Angleur, Liège, Liège Province, Belgium

Crystallography of Halloysite-7Å

Crystal System:Monoclinic
Class (H-M):m - Domatic
Cell Parameters:a = 5.14Å, b = 8.9Å, c = 14.9Å
β = 101.9°
Ratio:a:b:c = 0.578 : 1 : 1.674
Unit Cell Volume:V 666.97 ų (Calculated from Unit Cell)
Comment:Space group Cc.

Chemical Properties of Halloysite-7Å

Formula:
Al
 
2
(Si
 
2
O
 
5
)(OH)
 
4
Simplified for copy/paste:Al2(Si2O5)(OH)4
Essential elements:Al, H, O, Si
All elements listed in formula:Al, H, O, Si

Relationship of Halloysite-7Å to other Species

Related Minerals - Nickel-Strunz Grouping):

- +
9.ED.05Dickite
Al
 
2
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.05Kaolinite
Al
 
2
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.05Nacrite
Al
 
2
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.05Odinite
(Fe,Mg,Al,Fe,Ti,Mn)
 
2.4
((Si,Al)
 
2
O
 
5
)(OH)
 
4
9.ED.10Halloysite
Al
 
2
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.10Hisingerite
Fe
3+
2
(Si
 
2
O
 
5
)(OH)
 
4
· 2H
 
2
O
9.ED.15Amesite
Mg
 
2
Al(AlSiO
 
5
)(OH)
 
4
9.ED.15Antigorite
Mg
 
3
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.15Berthierine
(Fe
2+
 
,Fe
3+
 
,AlMg)
 
2-3
((Si,Al)
 
2
O
 
5
)(OH)
 
4
9.ED.15Brindleyite
(Ni,Al)
 
3
(Si,Al)
 
2
O
 
5
(OH)
 
4
9.ED.15Caryopilite
(Mn,Mg)
 
3
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.15Chrysotile
Mg
 
3
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.15Cronstedtite
Fe
2+
2
Fe
3+
 
((Si,Fe
3+
 
)
 
2
O
 
5
)(OH)
 
4
9.ED.15Fraipontite
(Zn,Al)
 
3
((Si,Al)
 
2
O
 
5
)(OH)
 
4
9.ED.15Greenalite
Fe
 
2-3
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.15Kellyite
Mn
2+
2
Al(AlSiO
 
5
)(OH)
 
4
9.ED.15Lizardite
Mg
 
3
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.15Manandonite
LiAl
 
4
(BSi
 
3
O
 
10
)(OH)
 
6
9.ED.15Népouite
(Ni,Mg)
 
3
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.15Pecoraite
Ni
 
3
(Si
 
2
O
 
5
)(OH)
 
4
9.ED.15Guidottiite
Mn
 
2
Fe
3+
 
(Fe
3+
 
SiO
 
5
)(OH)
 
4
9.ED.20Allophane
(Al
 
2
O
 
3
)(SiO
 
2
)
 
1.3-2
· 2.5-3H
 
2
O
9.ED.20Chrysocolla
Cu
 
2-x
Al
 
x
(H
 
2-x
Si
 
2
O
 
5
)(OH)
 
4
· nH
 
2
O (x < 1)
9.ED.20Imogolite
Al
 
2
SiO
 
3
(OH)
 
4
9.ED.20Neotocite
(Mn,Fe,Mg)SiO
 
3
· H
 
2
O
9.ED.25Bismutoferrite
Fe
3+
2
Bi(SiO
 
4
)
 
2
(OH)
9.ED.25Chapmanite
Fe
3+
2
Sb
3+
 
(SiO
 
4
)
 
2
(OH)

Other Names for Halloysite-7Å

Synonyms:
Dehydrated halloysiteMetahalloysite
Other Languages:
Simplified Chinese:变叙永石

Other Information

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

References for Halloysite-7Å

Reference List:

- +
Berthier (1826)

American Mineralogist 39 (1954), 97

American Mineralogist 40 (1955), 1110

Acta Crystallographica B31 (1975), 2851

Clays and Clay Minerals 26 (1978), 25

Powder Diffraction 4 (1989), 19

Clays and Clay Minerals (1991): 39: 113.

Handbook of Mineralogy (Anthony et al.), 2 (1995), 311




Internet Links for Halloysite-7Å

Search Engines:
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  • External Links:
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  • Look for Halloysite-7Å on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
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  • Localities for Halloysite-7Å

    The 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. ? 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.
    Belgium
     
    • Liège Province
      • Liège
    Ann.Chim.Phys., sér. 2 (1826) 32, 332-335
    China
     
    • Fujian Province
      • Xiamen Prefecture
        • Tong'an District
    Mao Xingli and Yan Yipeng (1987): Journal of Fuzhou University, Natural Sciences Edition 15(3); Acta Petrologica et Mineralogica 11(2), 146-156 (1992)
    • Guangxi Zhuang Autonomous Region
      • Baise Prefecture
        • Pingguo Co.
    Zhongcao Liang (1983): Geology and Prospecting 19(8), 24-28; Xinyu Cao and Tongjiang Tang (1986): Geology and Prospecting 22(2), 18-23
    • Hunan Province
      • Huaihua Prefecture
        • Chenxi Co.
    Shu-Gen Zhang, Xiao-Hu Liu, and Jun Ding (2006): Acta Petrologica et Mineralogica [Yanshikuangwuxue Zazhi] 25(5), 433-439.
    • Jiangsu Province
      • Suzhou Prefecture
        • Huqiu District
    Kecong Han and Shengyun Ma (1985): Mineral Deposits 4(2), 58-68
    Denmark
     
    • Faroe Islands
      • Suðuroy Island
        • Hvalba
    Weisenberger, T. B. & Spürgin, S. (2012): Die Färöer - ein geologischer Streifzug. Aufschluss 63, 173-192.
    Germany
     
    • Rhineland-Palatinate
      • Eifel
        • Laach lake volcanic complex
          • Mendig
            • Niedermendig
    Blass, G.; Graf, H.W., Neue Mineralienfunde aus der Eifel und dem Siegerland, Mineralien-Welt 10/3, 23, 1999
    Blass, G.; Graf, H.W., Neue Mineralienfunde aus der Eifel und dem Siegerland, Mineralien-Welt 10/3, 23, 1999
      • Siegerland
        • Gebhardshain
          • Kausen
    Wittern: "Mineralfundstellen in Deutschland", 2001
    Greece
     
    • Attikí Prefecture (Attica; Attika)
      • Lavrion District (Laurion; Laurium)
        • Lavrion District Mines
          • Agios Konstantinos [St Constantine] (Kamariza)
    Möckel, S. (2000): Strashimirit und 11 weitere Neubestimmungen aus Lavrion (GR). Lapis 25 (7-8), 74.
          • Sounion area
            • Agia Varvara Mines (St Barbara Mines)
    Möckel, S. (2000): Strashimirit und 11 weitere Neubestimmungen aus Lavrion (GR). Lapis 25 (7-8), 74.
    Indonesia
     
    • Jawa Island (Java Island)
      • Jawa Barat Province (West Java Province)
        • Bogor District
    Milési, J.P., Marcoux, E., Sitorus, T., Simandjuntak, M., Leroy, J., and Bailly, L. (1999): Mineralium Deposita 34, 131-149.
    Italy
     
    • Sardinia
      • Cagliari Province
        • Sarroch
    - Orlandi, P., Gelosa, M., Bonacina, E., Caboni, F., Mamberti, M., Tanca, G., A. et Vinci, A. (2013) : Sardignaite, gelosaite et tancaite-(Ce) : trois nouveaux minéraux de Su Seinargiu, Sarroch, Sardaigne, Italie. Le Règne Minéral, 112, 39-52.
    New Zealand
     
    • Kermadec Islands
    Muiruru F.G. (1985) Hot spring and rock samples from Curtis Island Volcano, Kermadec Group. Unpub. paper Geothermal Institute, University of Auckland
    Peru
     
    • Cajamarca Department
      • Cajamarca Province
        • Cajamarca
    Dill, H.G., Bosse, H.-R., Henning, K.-H., Fricke, A., and Ahrendt, H. (1997): Mineralium Deposita 32, 149-163.
    Russia
     
    • Urals Region
      • Southern Urals
        • Orenburgskaya Oblast'
          • Dombarov District
    Gorbachev, B.F., Sharapov, A.F., Lyadskii, P.V., and Shmel'kov, N.T. (2004): The South Ushkoty Eluvial Kaolin Deposit in the Southeastern Orenburg Region. Lithology and Mineral Resources 39(5), 412-424.
          • Svetlyi
            • Buruktal District
              • Buruktal massif
    Talovina, I.V., Lazarenkov, V.G., and Vorontsova, N.I. (2003): Lithology and Mineral Resources 38(5), 403-415.
    USA
     
    • Alabama
      • De Kalb Co.
    Thomas F.Bates,Fred A.Hilderband and Ada Swineford (1950) Morphology and Structure of Endellite and Halloysite.The American Mineralogist Vol.35,July-August 1950,No.7-8
    • Maine
      • Oxford Co.
        • Paris
    King, V. T. and Foord, E. E., 1994, Mineralogy of Maine, Descriptive Mineralogy, volume 1, Maine Geological Survey, Augusta, Maine, USA, pp. 418 + 88 plates.
    • North Carolina
      • Catawba Co.
    Bates,Thomas F.,Hiderbrand,Fred A.,and Swineford,Ada.,(1950) Morphology and Structure of Endellite and Halloysite: The American Mineralogist,Vol.35,July-August,1950,No.7-8
    Bates,Thomas F.,Hiderbrand,Fred A.,and Swineford,Ada.,(1950) Morphology and Structure of Endellite and Halloysite :The American Mineralogist ,Vol.35.July-August,1950,No.7-8
      • Jackson Co.
    Bates,Thomas F.,Hiderbrand,Fred A.,and Swineford,Ada (1950) Morphology and Structure of Endellite and Halloysite : The American Mineralogist,Vol.35,July-Aug,1950,No.7-8
      • Macon Co.
        • Cowee Valley
          • Ellijay District
            • Franklin
    Clays and Clay Minerals,39 and 113, 1991
      • Mitchell Co.
        • Spruce Pine District
          • Spruce Pine
    Johnson,Sheryl L.,Guggenheim,Stephen and Van Groos,A.F Koster (1990)Thermal Stability of Halloysite by High-Pressure Differential Thermal Analysis :Clay and Clay Minerals,Vol.38,No.5,pg.477-484,1990
    • Texas
      • Real Co.
    Thomas F.Bates,Fred A.Hilderband and Ada Swineford (1950) Morphology and Structure of Endellite and Halloysite. The American Mineralogist Vol.35: July-August 1950,No.7-8
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