Macaulayite

General Information: Chemical Formula:(Fe+++,Al)24Si4O43(OH)2 Composition:(Molecular Weight = 2,116.93 gm)Aluminum 2.55 % AlIron 58.04 % FeSilicon 5.31 % SiHydrogen 0.10 % H Oxygen 34.01 % O  Empirical Formula: Fe3+22Al2Si4O43(OH)2 Environment:Deeply weathered granite. IMA Status:Approved IMA 1981 Locality:Bennachie car park, 7 km NW of Inverurie, Aberdeenshire, Scotland. Name Origin:Named for the Macaulay Institute for Soil Research.Physical Properties: Cleavage:[001] Good Color:blood red. Density:4.41 Habits:Earthy - Dull, clay-like texture with no visible crystalline affinities, (e.g. howlite)., , Luster:Earthy (Dull) Streak:light redMore details...