﻿258 Frof. Milne and Alex. Murray — Rochs of Newfoundland. 



to be seen, whilst magnetic iron, and probably also chromic iron, are 

 disseminated through the mass. Enstatite, diallage, and bronzite 

 have also been observed. 



The chloritic rocks are sometimes slaty in their character, and 

 sometimes compact and earthy. Very often these rocks are talcose, 

 and in their joints calcareous. Grains of magnetite are to be seen in 

 the mass. Some of them give indications of having been derived 

 from diorites. Associated with this series are a number of rocks 

 which are also, but to a much less degree, chloritic. Amongst them, 

 we have altered felsites of a light-green colour, some of which show 

 changes approaching serpentine. There are also others of a green 

 colour, which are tolerably compact, but which under the microscope 

 apparently resolve themselves into a volcanic ash or breccia. In 

 some cases the angular and sub-angular fragments of which these 

 rocks are made up are easily to be recognized. Distinct traces of 

 crystals of felspar are also to be made out. 



Amongst these rocks, bands or beds of dolomite are occasionally 

 found, associated with which at Tilt Cove there is an irregular 

 deposit of copper-nickel. It is in the form of small strings and 

 nests. With the chloritic rocks irregular deposits of copper pyrites 

 occur ; this has led, in the case of Tilt Cove, to the opening of a 

 large and prosperous mine. 



Further to the north, at Terra Nova Mine, a similar series of 

 rocks is to be met with. Here the predominating metallic ore is 

 iron pyrites, which occurs in a band about five feet in thickness. 



Although sedimentary rocks are exhibited in the district, volcanic 

 rocks nevertheless predominate and give a character to the whole. 

 That in Silurian times we had volcanos of large extent may alone be 

 inferred from the existence of the extensive beds which I have 

 called volcanic ash and breccia. Since that period, however, the 

 rocks have been so changed in character that it is with difficulty, 

 and generally speaking only with the aid of the microscope, that their 

 origin is to be inferred. 



Along the north side of Hare Bay we find a compact splintery 

 grey slate, which at many points holds finely disseminated iron 

 pyrites, which is also sometimes in veins. Near the head of the 

 Bay, at How Harbour, true serpentinous I'ocks rise conspicuously into 

 high hills, which have generally a bare appearance and a character- 

 istic I'eddish tinge. ' Some specimens from this locality had a splintery 

 fracture and a fibrous structure. With the ^" objective, kaolinized 

 felspar, crystalline grains of hornblende and crystals of magnetic 

 iron were distinctly visible, giving altogether indications of an 

 altered diorite. Other specimens showed a striking likeness to some 

 of those from Gander River Valley, 160 miles to the south. 



On the western side of the island, commencing at Bonne Bay, are 

 some very high flat-topped hills, which, from their reddish colour 

 and bare surfaces, are at once to be recognized as being serpentinous. 

 To the south of this, in Lark Harbour, we find rocks belonging to 

 this series of a very undefinable character, — they are rusty, ar- 

 gillaceous, and filled with so many joints that it is difficult to obtain 



