396 



Transactions. — Geo logy . 



It has been collected from Red Hill, Collingwood, by Dr. Hector (Col. 

 Mus. & Lab. Rep., xiii., p. 35). 



Bronzite, Mg (Fe) Si. — The occurrence of this mineral in diorite rocks 

 of the West Coast is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 

 1865, pp. 266, 438), and by Mr. E. H. Davis at the Dun Mountain (Geol. 

 Rep. 1870-71, p. 112). A specimen from the Dun Mountain in the collec- 

 tion of the Colonial Museum consists of crystals of a brownish-green colour 

 imbedded in a network of veins of picrosmine. 



Hydrous Silicates of Magnesia and Lime. 



Meerschaum, 2 Mg 2 Si 3 + 3 H. — The occurrence of this mineral at the 

 Dun Mountain is mentioned (Col. Mus. & Lab. Rep., vi., p. 16), the speci- 

 men having been collected by the late Mr. E. H. Davis. " Its colour was 

 pure white, lustre feeble, opaque, structure amorphous ; to the touch it has 

 that soft smoothness peculiar to minerals of this class ; hardness 2 to 3 ; 

 easily decomposed by hydrochloric acid. It occurs in contact with massive 

 white quartz, enclosing columnar detached crystals of a dark green colour, 

 probably hypersthene." Its composition is — 



Silica 53-76 



Lime 



Alumina . . 



Iron oxides 



Magnesia 



Water of constitution 



2-36 



4-35 



traces 



20-36 



19-17 



100-00 



Dermatin,(Mg,Fe) Si + 2 H. — This mineral is mentioned by Mr. E. 

 H. Davis (Geol. Rep., 1870-71, p. 112) as occurring in thin faces with 

 smooth polished surfaces at the Dun Mountain. 



Talc, Mg s Si 4 + H. — The occurrence of this mineral is mentioned by 

 Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 438) in quartz from the "West 

 Coast Sounds; and again by Mr. D. Macfarlane (Geol. Rep., 1876-77, p. 

 27) at Jackson's Bay. There are specimens in the collection of the Colonial 

 Museum from Collingwood and Jackson's Bay, both being of a pale green 

 colour. It is somewhat widely distributed on the West Coast of the South 

 Island, being frequently found associated with the crystalline rocks of that 

 district. 



Steatite is mentioned by Dr. Hector at Milford Sound (Jurors' Rep. N.Z. 

 Ex., 1865, pp. 266, 437), and it occurs in considerable quantities at Col- 

 lingwood hi a massive form and of a grey pink and green colour ; some 

 specimens are foliated. Its position is shown on the geological map of 

 Collingwood published by Dr. Hector (Geol. Rep., 1873-74, p. iv.) 



