Feroxyhyte | |
---|---|
General | |
Category | Oxide mineral |
Formula (repeating unit) | δ-Fe3+O(OH) |
IMA symbol | Fox[1] |
Strunz classification | 4.FE.40 |
Dana classification | 06.01.04.04 |
Crystal system | Hexagonal Unknown space group |
Unit cell | a = 2.95, c = 4.56 [Å]; Z = 1 |
Identification | |
Formula mass | 88.85 g/mol |
Color | Brown, yellow-brown |
Crystal habit | Concretionary, massive, nodular |
Streak | Yellow |
Diaphaneity | Opaque |
Specific gravity | 4.31 |
Density | 4.2 |
Optical properties | Uniaxial |
References | [2][3][4] |
Feroxyhyte is an oxide/hydroxide of iron, δ-Fe3+O(OH). Feroxyhyte crystallizes in the hexagonal system. It forms as brown rounded to concretionary masses. Feroxyhyte is opaque, magnetic, has a yellow streak, and has a relative density of 4.2.[3]
It occurs in manganese-iron nodules on the Atlantic and Pacific Ocean floors. It is also found in the Baltic, White, and Kara Seas.[5] Forms under high pressure conditions and reverts to goethite on exposure to surface conditions.[3] It also occurs as cement and coatings on clasts in poorly drained soils and sediments, formed by the rapid oxidation of iron(II) oxide compounds.[5]
It was first described in 1976 for an occurrence in soils at its type locality: Kolomyya, Ivano-Frankivsk Oblast, Ukraine.[2][5]
References
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b "Feorxyhyte mineral information and data". Mindat.org. Retrieved 2011-10-24.
- ^ a b c "Feroxyhyte Mineral Data". Webmineral.com. Retrieved 2011-10-24.
- ^ "Information card - FEROXYHYTE". Mineral Crystal Structure Database. Retrieved 2011-10-24.
- ^ a b c "Handbook of Mineralogy" (PDF). Archived from the original (PDF) on 2021-02-27. Retrieved 2011-10-24.