Halloysite [ Al2Si2O5(OH)4 ]
Image of Halloysite
Image of Kaolinite, Albite, Halloysite (var. hkl), Illite-Smectite 12.0A, Montmorillonite, Orthoclase and Quartz in specimen 'API13 Kaolinite / Halloysite' [CSIRO].
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Material properties
| Formula | Al2Si2O5(OH)4 |
| Abbreviation | Hly-7Å |
| Variant | hkl |
| Classifications | Minerals containing OH, Kaolinite (subgroup) |
| Luminescence emitter | Triplet-singlet |
| IMA Status | Grandfathered (pre-IMA), 1826 |
| Search other databases | webmineral.com, mindat.org, rruf.info, mineralienatlas.de, Handbook of Mineralogy, American Mineralogist Crystal Structure Database |
| Related materials | Dickite, Halloysite-7Å, Kaolinite, Nacrite |
| Crystal symmetry | Monoclinic, Point group m, Space group Cc (#9) |
| Tags | Hydroxide, Hydroxide , Mineral, Aluminosilicate |
Composition
| Element | Atoms |
|---|---|
| O | 9 |
| Al | 2 |
| Si | 2 |
| H | 4 |
| Total: | 17 |
Specimens of Halloysite
| Name | Owner | Materials | Phase purity | Image |
|---|---|---|---|---|
| API13 Kaolinite / Halloysite | CSIRO | Albite, Halloysite, hkl (34.9%), Illite-Smectite 12.0A, Kaolinite, Montmorillonite, Orthoclase, Quartz | 34.9 |