180 THE ROYAL SOCIETY OF CANADA 



Plates. 



The plates are reproductions from photographs of a series of 

 specimens taken across the contact between a zone of garnet, formed 

 by contact metamorphism, and the granodiorite country rock, Iron 

 Chancellor claim. Pass Creek, Boundary District. The photographs 

 are by L. L. Bolton and are about natural size. 



Plate I, Fig. 1. Granodiorite from edge of garnet mass. 



Fig. 2 . Same rock but with small green garnet crystals developing. 

 The dark masses are garnet. This shows the first stage in alteration 

 to garnet mass. 



Plate II, Fig. 3. Same but alteration more extensive as the zone 

 of intense metamorphism is approached. The light portions are 

 garnet ; the dark is the granodiorite host, somewhat altered to pyroxene 

 and orthoclase. 



Fig. 4. Same. Process further developed ; the crystals are larger 

 and individuals have coalesced; little of the original host remains. 

 Note the zonal structure of the garnets. 



Plate III, Fig. 5. Same, approaching the massive garnet. The 

 residue of the host is restricted to small interstitial fillings between 

 garnet individuals. The garnet crystalon the left shows a core of 

 granodiorite. 



