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Régnier - I have also seen a number of individual samples in which
Ms+St+Crd+Bt appear together, seemingly in equilibrium. Some pictures
appear in the paper referenced below. In my experience, Crd generally
surrounds or from other criteria is generally late texturally compared to
the St and when present andalusite, although in some cases it is very hard
to say one way or the other. If it weren't for some pretty serious
topological problems that arise in in the metapelite grid when you treat
this as a stable assemblage, there would seem to be no reason to doubt its
stability. This is why we emphasized having to examine the assemblage in
its broader context. The arguments are in the paper. Returning to your
sample, I would check that there is stable Ms in it (if not, that changes
everything), and entertain the possibility of unstable persistence of St
into a  lower pressure Crd-bearing assemblage.

>Dear All,
>
>In relation with the paper from Pattison and al  " polymetamorphic origin
>of muscovite + cordierite + Staurolite + biotite " (1999), I would like to
>know yours opinions about this thins section (attachment) found in " la
>Montagne Noire " (France) where the equilibrium at Tmax seems to be obvious.
>Do you know some other examples like this?
>
>Sincerely
>______________________________
>
>Régnier Jean-Luc
>Johannes Gutenberg-Universität
>Institut für Geowissenschaften, FB 22
>Graduiertenkolleg
>Becherweg 21, 55099 Mainz
>tel: (0049)-6131-39-24767 (office)
>tel: (0049)-6131-216469 (home)


David R.M. Pattison, Department of Geology and Geophysics,
University of Calgary, Calgary, Alberta, T2N 1N4, Canada.
Phone: 403-220-3263 (my office); 403-220-5841 (dept. office)
Fax: 403-284-0074     email: [log in to unmask]