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 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
StatisticsThe ElementsMember 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

Allophane

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

Mosset rare earths deposit, Mosset, Pyrénées-Orientales, Occitanie, France
Allophane

Kamariza Mines Agios Konstantinos [St Constantine] Lavrion District Mines, Lavrion District Attikí Prefecture Greece
Allophane

Maid of Sunshine Mine, Turquoise District Dragoon Mts, Cochise Co., Arizona, USA
Allophane

Mosset rare earths deposit, Mosset, Pyrénées-Orientales, Occitanie, France
Allophane

Kamariza Mines Agios Konstantinos [St Constantine] Lavrion District Mines, Lavrion District Attikí Prefecture Greece
Allophane

Maid of Sunshine Mine, Turquoise District Dragoon Mts, Cochise Co., Arizona, USA
Allophane

Mosset rare earths deposit, Mosset, Pyrénées-Orientales, Occitanie, France
Allophane

Kamariza Mines Agios Konstantinos [St Constantine] Lavrion District Mines, Lavrion District Attikí Prefecture Greece
Formula:
(Al2O3)(SiO2)1.3-2 · 2.5-3H2O
System:
Amorphous
Colour:
White, pale blue to ...
Lustre:
Waxy
Hardness:
3
Name:
From the Greek άλλος ("allos") for "other" or "different" and φαίνεσθαι ("phaenesthai"), "to appear", in allusion to the change it undergoes in a blowpipe flame.
Amorphous hydrous silicate of aluminium, composition not fixed. Principal member of the nominal "Allophane Group."
Copper-bearing varieties can be confused with chrysocolla.
Colourless varieties may be confused with hyalite.

The nano-sized particles have a ball-shaped morphology.

Related to imogolite.


Classification of Allophane

IMA status:
Approved, 'Grandfathered' (first described prior to 1959)
Strunz 8th ed.:
8/H.26-10
Nickel-Strunz 10th (pending) ed.:
9.ED.20

9 : SILICATES (Germanates)
E : Phyllosilicates
D : Phyllosilicates with kaolinite layers composed of tetrahedral and octahedral nets
Dana 7th ed.:
71.1.5.1
Dana 8th ed.:
71.1.5.1

71 : PHYLLOSILICATES Sheets of Six-Membered Rings
1 : Sheets of 6-membered rings with 1:1 layers
Hey's CIM Ref.:
15.11

15 : Silicates of Aluminum

Physical Properties of Allophane

Lustre:
Waxy
Diaphaneity (Transparency):
Transparent, Translucent
Colour:
White, pale blue to sky-blue, green, brown
Streak:
White
Hardness (Mohs):
3
Tenacity:
Brittle
Cleavage:
None Observed
None
Fracture:
Conchoidal

Chemical Properties of Allophane

Formula:
(Al2O3)(SiO2)1.3-2 · 2.5-3H2O
IMA Formula:
Al2O3(SiO2)1.3-2.0 · 2.5-3.0H2O
Elements listed in formula:
Al, H, O, Si - search for minerals with similar chemistry
Common Impurities:
Ti,Fe,Mg,Ca,Na,K

Crystallography of Allophane

Crystal System:
Amorphous
Morphology:
Rarely observed as ring-shaped particles, with diameters of 50 ºA, which in three dimensions may represent sections through hollow spherules or polyhedra. As hyaline crusts and masses; stalactites and flowstones.

Occurrences of Allophane

Type Occurrence of Allophane

Type Locality:
Gräfenthal, Thuringian Forest, Thuringia, Germany
Place of Conservation of Type Material:
Mining Academy, Freiberg, Germany, 26104.

Relationship of Allophane to other Species

Common Associates:
Chrysocolla
Cristobalite
Gibbsite
Imogolite
Limonite
Quartz
Vermiculite
Related Minerals - Nickel-Strunz Grouping):
9.ED.Clinochrysotile
9.ED.05DickiteAl2(Si2O5)(OH)4
9.ED.05KaoliniteAl2(Si2O5)(OH)4
9.ED.05NacriteAl2(Si2O5)(OH)4
9.ED.05Odinite(Fe,Mg,Al,Fe,Ti,Mn)2.4((Si,Al)2O5)(OH)4
9.ED.10HalloysiteAl2(Si2O5)(OH)4
9.ED.10HisingeriteFe23+(Si2O5)(OH)4 · 2H2O
9.ED.10Halloysite-7ÅAl2(Si2O5)(OH)4
9.ED.15AmesiteMg2Al(AlSiO5)(OH)4
9.ED.15AntigoriteMg3(Si2O5)(OH)4
9.ED.15Berthierine(Fe2+,Fe3+,Al)3(Si,Al)2O5(OH)4
9.ED.15Brindleyite(Ni,Al)3(Si,Al)2O5(OH)4
9.ED.15CaryopiliteMn32+Si2O5(OH)4
9.ED.15ChrysotileMg3(Si2O5)(OH)4
9.ED.15CronstedtiteFe22+Fe3+((Si,Fe3+)2O5)(OH)4
9.ED.15Fraipontite(Zn,Al)3((Si,Al)2O5)(OH)4
9.ED.15Greenalite(Fe2+,Fe3+)2-3Si2O5(OH)4
9.ED.15KellyiteMn22+Al(AlSiO5)(OH)4
9.ED.15LizarditeMg3(Si2O5)(OH)4
9.ED.15ManandoniteLi2Al4(Si2AlB)O10(OH)8
9.ED.15Népouite(Ni,Mg)3(Si2O5)(OH)4
9.ED.15PecoraiteNi3(Si2O5)(OH)4
9.ED.15GuidottiiteMn2Fe3+(Fe3+SiO5)(OH)4
9.ED.20ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
9.ED.20ImogoliteAl2SiO3(OH)4
9.ED.20Neotocite(Mn,Fe,Mg)SiO3 · H2O
9.ED.25BismutoferriteFe23+Bi(SiO4)2(OH)
9.ED.25ChapmaniteFe23+Sb3+(Si2O5)O3(OH)
Related Minerals - Hey's Index Grouping:
15.1AndalusiteAl2(SiO4)O
15.2KyaniteAl2(SiO4)O
15.3SillimaniteAl2(SiO4)O
15.4MulliteAl4+2xSi2-2xO10-x
15.5PyrophylliteAl2Si4O10(OH)2
15.6DickiteAl2(Si2O5)(OH)4
15.7NacriteAl2(Si2O5)(OH)4
15.8KaoliniteAl2(Si2O5)(OH)4
15.9MetahalloysiteAl2(Si2O5)(OH)4
15.10HalloysiteAl2(Si2O5)(OH)4

Other Names for Allophane

Synonyms:

Allophanite

Elhuyarite

Ilbaite

Razoumofskyn

Razumofskin

Riemanite

Riemannite

Name in Other Languages:
Italian:Allofane
Simplified Chinese:水铝英石
Traditional Chinese:水鋁英石
Varieties:

Allophane-evansite

Cupro-Allophane

Ferriallophane

Phosphate-Allophane

Plumballophane

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 Allophane

Reference List:
Hausmann, J.F.L., Stromeyer, F. (1816) Über Silberkupferglanz und Allophan. Göttingische Gelehrte Anzeigen: 2: 1251-1253.

Snetsinger, K.G. (1967) High-alumina allophane as a weathering product of plagioclase. American Mineralogist: 52: 254-262.

Kitagawa, Y. (1974) Dehydration of allophane and its structural formula. American Mineralogist: 59: 1094-1098.

Henmi, T., Wada, K. (1976) Morphology and composition of allophane. American Mineralogist: 61: 379-390.

Wada, S.I., Wada, K. (1977) Density and structure of allophane. Clay Minerals Bulletin: 12: 289-298.

Bailey, S.W. (1980) Summary of recommendations of AIPEA nomenclature committee on clay minerals. American Mineralogist: 65: 1-7.

Parfitt, R.L., Furkert, R.J., Henmi, T. (1980) Identification and structure of two types of allophane from volcanic ash soils and tephra. Clays and Clay Minerals: 28: 328-334.

van der Gaast, S.J., Wada, K., Wada, S.I., Kakuto, Y. (1985) Small-angle X-ray powder diffraction, morphology, and structure of allophane and imogolite. Clays and Clay Minerals: 33: 237-243.

Gaines, R.V., H. Skinner, C.W., Foord, E.E., Mason, B., Rosenzweig, A. (1997) Dana's New Mineralogy : The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana: eighth edition. John Wiley and Sons, Inc., 1819 pp.: 1432.

Internet Links for Allophane

mindat.org URL:
https://www.mindat.org/min-139.html
Please feel free to link to this page.
Search Engines:
  • Look for Allophane on Google
  • Look for Allophane images on Google
    • External Links:
  • Look for Allophane on Webmineral
  • Look for Allophane on Wikipedia
  • Look for Allophane on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Handbook of Mineralogy page PDF
    • Mineral Dealers:
  • Buy from McDougall Minerals
  • Buy from David K Joyce minerals
  • The Arkenstone - Fine Minerals
  • Fine Minerals from Weinrich Minerals, Inc.
  • Buy RARE Minerals from Rocks of Africa
  • Quality Minerals at Fair Prices
  • MINSERVICE - buy on www.minservice.com - Worldwide Classical and Rarity
  • Buy rare minerals from Excalibur Minerals
  • Buy minerals from YourMineralCollection
  • Rare and Unusual minerals at Mineralogical Research Company
  • High-end worldwide specimens & outstanding customer service
  • Allophane specimens for sale - minfind.com
  • Top quality minerals from Kristalle of California
    • Specimens:
    The following Allophane specimens are currently listed for sale on minfind.com.

    Localities for Allophane

    Show Locality List (488 Items)
    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 1993-2017, 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: June 27, 2017 23:32:10 Page generated: June 26, 2017 23:09:49
    Go to top of page