109 



" I think there are very few who would agree with Dr. Hunt in 

 the general proposition that the cliorites and serpentines of the Quebec 

 group are of sedimentary origin . . . . " 



Most of these serpentines however are almost always associated 

 with dioritic rocks of which Dr. Ells reported as follows in 1885 : 



" Dioritic rocks are found at many points throughout the Town- 

 ships, sometimes in masses of large extent, as in the Big Ham and 

 Little Ham Mountains, and in the peaks along the western side of Lake 

 Memphremagog; at others, as bosses and dykes. With these are often 

 associated dioritic agglomerates, serpentines and serpentinous breccias." 



In places massive serpentines are in immediate contact with black 

 slates, and in others, very much broken and slaty serpentines, different 

 in character, in colour and in touch, are found in what appear to be 

 exactly the same black slates. To say that all the Eastern Township 

 serpentines are or are not intrusive is a question that can be solved only 

 after a long and very careful study of the whole region. There are un- 

 doubtedly two very distinct sets of serpentines in this field, but whether 

 their difference is due to age, or origin, or both, is still an unsolved 

 problem. 



These serpentines are generally darker coloured, tougher and better 

 fitted for ornamental purposes than those of the Laurentian series. 

 Ophiolites, which are chiefly mixtures of limestone or of dolomite and 

 serpentine, the latter predominating, are found in many places in the 

 Eastern Towships. 



Many minerals of great importance are found either associated or 

 in close proximity to serpentine in this region, and in order to show the 

 importance attached to the study of this class of rocka, an idea of the 

 economic value of these will be given. 



The old Huntington copper mine, in the Tonship of Bolton, is just in 

 the midst of serpentine and serpentinous rocks ; the Brompton Lake 

 copper mine, in the Township of Orford, is also located in the serpent- 

 ine. Variegated and vitreous sulphurets of copper disseminated in 

 small masses in a bed of grey tough serpentine rock, four feet in width 

 and flanked by serpentine on each side, occur on lot 28, ran^e 9, 

 Brompton. According to the Crown Land survey, a quartzose chloritic 

 rock near a band of serpentine, in Orford, contains a small amount of 



