OCCURRENCE OF TINGUAITE AT KOSCIUSKO, N.S.W. 355 



W. H. Twelvetrees 1 and W. F. Petterd have described an 

 exceedingly interesting series of nepheline, anorthoclase, nosean 

 segirine rocks in the neighbourhood of Port Cygnet, Tasmania. 

 Melanite garnet and fluorite are present in some varieties : in some 

 cases sanidine takes the place of anorthoclase. Messrs. Twelvetrees 

 and Petterd class these as solvsbergites nosean trachytes, and 

 tinguaite porphyries. 



As regards the occurrence of nepheline in Australia, it has 

 hitherto been described only as an accessory mineral. Professor 

 Ulrich has recorded 2 it in an "older basalt" (Eocene ?) at Phillip 

 Island, Bass' Strait, Victoria. Analcime and natrolite occur in 

 abundance as zeolites in this lava. F. M. Krause 3 also records 

 nepheline from Victoria, at Western Port. 



Recently Prof. J. W. Gregory 4 has described an interesting 

 series of solvsbergites and trachy-phonolites containing anortho- 

 clase, nosean, segirine, riebeckite, and in some cases cossyrite, from 

 Mt. Macedon, Yictoria. 



In Queensland, Mr. Dunstan of the Geological Survey has 

 referred 5 to a basalt rich in nepheline, at Mt. Beardmore, Dawson 

 River, west, He states that this rock "occurs as an isolated peak 

 surrounded by old sedimentary altered rocks and by tableland 

 sandstones. The rock is fine grained and contains nepheline, 

 augite, olivine, magnetite, etc.: no felspar present." He adds 

 that it looks fresh. 



In New South Wales, Prof. Liversidge 6 records the occurrence 

 of nepheline in amygdaloidal porphyry at "The Pinnacles," Co., 

 Forbes; JDowagarang and the Old Man Canobolas, near Wellington 



1 Trans. Aust. Inst. Mining Engineers, 1898, Vol. v., p. 108, and also 

 Papers and Proc. 1898-99, Eoy. Soc. Tasmania, pp. 3 - 26, figs. 1-8. 



2 Quoted by E. M. Johnston, Geology of Tasmania, 1888, p. 249. 



3 " An Introduction to the Study of Mineralogy for Australian readers," 

 F. M. Krause, 1896, p. 205. 



* Proc. Eoy. Soc, Victoria, Vol. xiv., (New Series) Pt. ii., pp. 185- 217, 

 Pis. xi. - xvii. 



5 Parliamentary Paper, No. C A. 9, 1901, Brisbane — Eep. Geol. Dawson 

 and Mackenzie Eivers, 1901, p. 28. Preliminary Note. 



6 Minerals of New South Wales — A. Liversidge, m.a., p.r.s., 1888, p, 185. 



