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?
Régnier Jean-Luc
Johannes Gutenberg-Universität
Institut für Geowissenschaften, FB 22
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.
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