MAGNETITE IRON DEPOSITS OF SOUTHEASTERN NEW YORK ye 
is not native to the Pochuck-Grenville. The pyrrhotite found in 
some of the deposits is likewise undoubtedly of magmatic origin. 
4 Sericite and related products are judged to be due to the action 
of the magmatic end-stage emanation concentrates on the minerals 
of the rock replaced, and hence to indicate magmatic control (see 
plate 6, figures 1, 3 and plate 7). 
