406 Transactions. — Geology. 



It was obtained from Dead-horse Gully, Lake Wakatipu, by Mr. McKay, 

 who states that it occurs on the strike of the Moke Creek copper lode. A 

 similar mineral has been forwarded by Mr. W. Docherty from Dusky Sound 

 where it occurs in gneiss. 



Orthoclase, .\\ Si 3 + K Si s , occurs as a constituent of the granites, 

 syenites, gneiss, tracbytes and rhyolites of New Zealand. It is mentioned 

 by Dr. Hector as occurring in all the schists and crystalline rocks of the 

 West Coast (Jurors' Eep. N.Z. Ex., 1865, pp. 266, 437), in granite from 

 the Auckland Islands, and in granite and hornblende rocks from Euapuke 

 (Trans. N.Z. Inst., vol. ii., pp. 183, 185), in dyke granite at Great Barrier 

 Island (Trans. N.Z. Inst., vol. ii, p. 375), and as sanidine in the trachyte 

 of the Sugar Loaves, Taranaki (Geol. Kep., 1866-67, p. 8) ; by Dr. v. 

 Hochstetter as sanidine in the rhyolitic tufas of Lake Taupo, and flesh- 

 coloured felspar in the syenite of the Boulder Bank, Nelson (New Zealand, 

 Eng. ed., pp. 385, 471) ; by Dr. v. Haast in the granite and other crystal- 

 line rocks of the West Coast, and as sanidine in the trachytes and trachy- 

 dolerites of Banks Peninsula (Jurors' Bep. N.Z. Ex., 1865, p. 257, and 

 Trans. N.Z. Inst., vol. xi., p. 504) ; and by B. Daintree, Esq., F.G.S., in 

 dolerite of the Hororata district and Acheron section ; in trachytic rocks at 

 Mt. Misery and Snowy Peak Bange and also in a granitic rock and 

 pitchstone at Snowy Peak Bange (Trans. N.Z. Inst., vol. vii., p. 458). The 

 specimens in the collection of the Colonial Museum are a pink variety in 

 granite from Dusky Sound, and a yellowish white specimen in a granitic 

 dyke from Great Barrier Island. 



Albite, -Al Si 3 + Na Si 3 , is mentioned by Dr. Hector in the diorites of 

 the West Coast (Jurors' Bep. N.Z. Ex., 1865, pp. 266, 437); by Dr. v. 

 Haast in dioritic porphyries of the Biver Wilkes and Makarora Banges 

 (Jurors' Bep. N.Z. Ex., 1865, p. 257); by Mr. E. H. Davis at the Dun 

 Mountain (Geol. Bep., 1870-71, p. 112); and by Prof. Liversidge from 

 George Sound (Trans. N.Z. Inst., vol. x., p. 498). There is a white 

 massive form, with chlorite, from Maori Point, Shotover, in the collection 

 of the Colonial Museum. 



Labradorite, J& Si 2 + (Ca, Na) Si, is mentioned by Dr. Hector in 

 trachydolerites from Flagstaff Hill (Jurors' Bep. N.Z. Ex., 1865, p. 487) 

 and by Dr. v. Haast in lava streams at Banks Peninsula (Jurors' Bep. 

 N.Z. Ex., 1865, p. 257), and in the basalts and as large crystals in the 

 dolerites of Banks Peninsula (Trans. N.Z. Inst., vol. xi., p. 499). There 

 is a specimen in the collection of the Colonial Museum from Purahanui, 

 Otago, of a dirty brown colour, showing play of colours on cleavage planes, 

 and another, of a grey colour, in dolerite from Mt. Charles, Otago. 



Saussnrite is mentioned by Dr. v. Haast in gabbro from Mt. Torlesse 

 Jurors' Bep. N.Z. Ex., 1865, p. 257). 



