BY H. I. JENSEN. Ill 



Sp. No.106. Glaucophane Rock. Loc: Leacy's Ck. 



i. The handspecimen is a dark, fine-grained rock, whose main 

 constituents are, respectively, deep bluish-green and light yellowish - 

 green. 



ii. Under the microscope it is seen to be a tine-grained, non- 

 crystalline, granular rock, made up essential]}'' of a light-coloured, 

 greenish-bine pleochroic glaucophane in fibrous irregularly - 

 terminated laths, and of a yellowish-brown epidote. Minute 

 quantities of felspar (orthoclase) and tremolite are also present. 

 This rock is therefore a Glaucophane-Epidote Rock. 



Sp. No.134. Glaucophane-Epidote Rock. Loc. : near Leacy's Ck. 

 Reserve, Mt. Mee Road. 

 This is another beautiful glaucophane-schist, in which the 

 glaucophane resembles that of Mt. Mee (Sp.65). 



Sp. No. 65. Glaucophane-Epidote Rock. Loc: Culvert Ck., Mt. 

 Mee (Plate xi., fig.3). 



i. In handspecimen a fine-grained, aphanitic dark rock, in 

 which bluish specks may be seen on close inspection or with a 

 pocket lens. 



ii. A noncrystalline, fine-grained schistose rock. 



Constituent minerals. — The rock is almost wholly made up of 

 epidote and glaucophane, which are present in about equal 

 amounts. The glaucophane is of a beautiful blue colour, highly 

 pleochroic, from deep violet-blue to greenish-blue, light sky-blue 

 and colourless, but green tints are rare. It occurs in irregularly 

 terminated laths. Sometimes a hornblendic cleavage may be 

 recognised. The epidote is of a honey-yellow colour, and slightly 

 pleochroic. Other minerals present are magnetite and tremolite. 



An analysis was made of this rock (Anal.xii. p. 169) and the 

 norm calculated (Norm xii. p. 17 1 ). It is noticeable that this 

 glaucophane-epidote rock, unlike most glaucophane-epidote rocks 

 hitherto analysed*, is very high in Fe 2 3 . Indeed, from the 

 fact that the rock contains nearly 50% of glaucophane, and from 



* See "A Chemical Study of the Glaucophane Schists," by Henry S. 

 Washington. Amer. Journ. Sci. Vol.xi. Jan. 1901. 



