and Igneous Rocks of Ensay. 83 



already described, composed of reddish felspar quartz and a 

 little mica or chlorite. As is commonly the case in the 

 schists at this place, pinite is plentiful in small dark olive- 

 green to blackish-green masses, and less frequently hexagonal 

 crystals. The sample which I examined from 16 is a light- 

 coloured crystalline compound of felspar, mica, chlorite, quartz, 

 and apatite, with some pinite. The felspars are better formed 

 crystals than is usually the case in these massive schists. 

 They are all more or less altered to pinite, small masses of 

 which are connected by veins running between the other 

 constituent minerals. The magnesia-mica is ragged-sided, 

 and in places crushed, and appears to be the first formed 

 mineral of this rock. It has been much chloritised in the 

 manner which I have already described. Crystalline-granular 

 epidote is associated with the chlorite, and also occurs 

 elsewhere in small spaces between other minerals. The 

 quartz fills in spaces as the latest formed of the constituents. 



This rock is one of the massive varieties of the schists, but 

 in this sample shows scarcely any traces of foliation. 



In following up the river from this place, there are small 

 cliffs of rock on the left-hand side which approach in character 

 some of the crystalline-granular, and some of the schistose 

 examples which I have now described. 



At 17 the rocks are crystalline granular, but contain 

 lenticular patches, such as I have spoken of as occurring also 

 in the schists ; one of these I observed to be composed of 

 fibrolite and quartz. 



At 18 the schists again show adjoining the crystalline.- 

 granular rocks. They are much contorted and are reticulated 

 with veins of red felspar, quartz, and pinite, or of quartz and 

 pinite only. It was at this spot that I collected the samples 

 of pinite for examination and analysis. The pinite veins 

 are between schist foliations, and thin out at each end. 



The colour of this pinite is dark green to greenish black 

 at the edges, or in thin splinters it is slightly translucent. 

 It is massive, or with a sub-micaceous cleavage, when the 

 mineral occurs in stout prisms. The lustre is waxy, except- 

 ing when there is an imperfect basal cleavage, when it 

 approaches a light pinchbeck colour. Hardness 2 to 2'5. 

 Before the blowpipe it fuses in splinters to a grey enamel. 

 The streak and powder are greyish white. It is partly 

 decomposed by hydrochloric acid. 



I found a few individuals showing crystalline planes, 

 and the most perfect one which I could extract from the 



g2 



