Talk:Gneiss
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Second picture looks like a migmatite, not gneiss. I think that it's better to remove it. Siim 19:30, 16 September 2005 (UTC)
Your article says that gneisses do not carry large quantities of micas, then it goes on to say that a gneiss may be classified as biotite gneiss. These two statements are contradictory because biotite is aI suck Mitchells dickBold textest deleting the reference to micas.
The article on biotite actually says that it is found in gneisses.
[edit] Mica
When shales and mudstones are metamorphosed they turn initially to slates and then to coarse-grained foliated rocks rich in shiny mica called schists, and finally to coarse-banded rocks called gneisses. The Geology of Britain, Peter Toghill.
I think this means that if it is foliated or in 'leaves' like a mica then it's a schist, if it is banded (maybe blocky?) it's a gneiss. I would appreciate comments and clarification here. PeterGrecian 12:22, 31 October 2006 (UTC)
