Mineral Factbook

Ferrihydrite

Fe3+10O14(OH)2IMA symbol: Fhyapproved

Ferrihydrite is an oxide or hydroxide mineral with the formula Fe3+10O14(OH)2, crystallizing in the trigonal system. It has a calculated density of 4.823 g/cm3.

Photos

Ferrihydrite specimen photo
Henk Smeets – tomeikminerals.com · CC BY 4.0 · Commons
Ferrihydrite specimen photo
Jerry Bigham, Ohio State University · CC BY-SA 3.0 · Commons
Ferrihydrite specimen photo
David Hospital · CC BY-SA 4.0 · Commons

Crystallography

Crystal systemtrigonal crystal systemWikidata (CC0)
Space groupP 63 m c
Cell (Å, °)a = 5.928, b = 5.928, c = 9.126; α = 90, β = 90, γ = 120
Cell volume277.733 ų, Z = 2
Axial ratios1.0000:1:1.5395calculated from COD 9011571
Source structureCOD 9011571 (Science, 2007) — 1 of 5 structures

Physical properties

Density (calculated)4.823 g/cm³calculated from COD 9011571

Classification

Nickel-Strunz (10th)4.FE.35Wikidata (CC0)
Nickel-Strunz (9th)4.FE.35Wikidata (CC0)