- Thanks to Peter
G.Seroka again for the Woolley book and for his own data.
- Francon Quarry (aka St.Michel
sill) is a silico-carbonatite sill in Trenton limestone. It is 2m
thick, and extends over an area of roughly 1.1x0.5 km. Chilled
contact zones reach a thickness of 4-5 cm. The rock, mainly in the
central and upper zones, contains many cm-sized vesicles, elongated
close to the contatcs. The chilled selvages are intergrowths of
dawsonite/feldspar with pseudos of dawsonite after analcime. The
central part also contains dawsonite pseudomorphs, feldspar laths,
dawsonites, other carbonates (partly calcite and dolomite). There
seems to be a second sill of 1.3 m below the main one.
- Mineral list: (still very
incomplete, bold =type loc.)
- Woolley, A.R.: Alkaline Rocks
and Carbonatites of the World. Part 1: North and South America.
British Museum (Natural History), London, 1987
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