136 GREAT SERPENTINE BELT OF NEW SOUTH WALES, iv., 



does not seem to be a clear boundary between the agglomerate 

 and the dolerite, and there is certainly no boundary between the 

 dolerite and an offshoot of spilitic magnetite-keratophyre, which 

 cuts across a second band of limestone, and opens out into a 

 roughly circular area of fine-grained, red-brown and highly 



Q^^z"^ 



--Hi^' 



Text-fig.5.— Silver Gully Complex, 

 vesicular (not slaggy), not very ferruginous magnetite-kerato- 

 phyre, which passes into a richly magnetitic slaggy rock. The 

 dolerite-sill may be traced for about half a mile to the north, 

 and the agglomerate at its western edge seems to grade into a 

 coarsely granular porphyritic quartz-keratophyre, which, on micro- 



