Feroxyhyte

Feroxyhyte is an oxide/hydroxide of iron, δ-FeO(OH). It occurs in manganese-iron nodules on the Pacific Ocean floor. Forms under high pressure conditions and reverts to goethite on exposure to surface conditions. 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.
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General Information:
 Chemical Formula:
Fe+++O(OH)
 Composition:
(Molecular Weight = 88.85 gm)
Iron 62.85 % Fe
Hydrogen 1.13 % H 
Oxygen 36.01 % O 
 Empirical Formula:
Fe3+OOH
 Environment:
Deep ocean (high pressure, low temperature, saltwater). Alters spontaeously to geothite on exposure to air.
 IMA Status:
Approved IMA 1976
 Locality:
Pacific ocean Fe-Mn nodules.
 Name Origin:
Named for the composition (Ferric, Oxygen, Hydroxide).
Physical Properties:
 Color:
brown.
 Density:
4.2
 Diaphaniety:
Opaque
 Habits:
Massive - Uniformly indistinguishable crystals forming large masses., Nodular - Tuberose forms having irregular protuberances over the surface., Concretionary - Rounded massive fine-g rained materials.
 Streak:
yellow
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