126 F. W. BUTTON. 



Trans. N.Z. Inst., Vol. xi., p. 503, and Geoloj^y of Canterbury, 

 p. 337. 



Sugar Loaves, Taranaki — A pale grey, vesicular rock, with 

 abundance of sanidine crystals and small black prisms of horn- 

 blende. Section : The ground-mass moderate, crystallitic, longu- 

 litie, but with numerous felspar microlites from -001 to -002 in 

 length, the glass is colourless. The porphyritic minerals are 

 sanidine, plagioclase, hornblende and magnetite. The felspars go 

 to -25 in length, they are zoned and with inclosures either central 

 or zonal ; the plagioclase is subordinate to the sanidine. The 

 hornblende is brown and goes up to -15 inch in length. Hector, 

 Progress Report Geol. Survey, 1866-7, p. 3. 



This is the rock of which the pier at Taranaki harbour is formed. 

 It occurs as a dyke cutting trachytic agglomerate. It sometimes 

 cmtains masses of nearly pure hornblende six or eight inches in 

 diameter. 



Wha7ujarei~A pale purplish-white rock with rather earthy 

 fracture, and with numerous small black specks scattered through 

 it. Section : Ground-mass abundant, colourless, and crystallitic, 

 but crowded with felspar microlites about -002 in length, and con- 

 taining small crystals of brown hornblende. The porphyritic 

 minerals are sanidine (-02), plagioclase (-015), hornblende ('06), 

 and a little biotite. There is no magnetite. The hornblendes are 

 brown, more abundant than the felspars, and shade off into the 

 hornblendes of the ground-mass. Brownish chlorite occurs after 

 hornblende. Occurs at Mt. Parahaki, a little east of Whangarei. 

 ■Cox, Reports Geol. Expl. 1876-7, p. 99. 



AuGiTE Trachyte. 



Bank's Peninsula — (1.) A darkish-grey compact rock with 

 scattered crystals of sanidine up to -25 in length. S.G. 2-53. 

 Section : Ground-mass very abundant, vitreous, crowded with 

 felspar microlites in laths and plates from -005 to -01 in length, a 

 few green augite microlites and specks of iron oxide. Shewing 

 fluxion. Th^ porphyritic minerals are sanidine, augite ,-ind a little 



n colours, scarce, up to "01 5 m 

 . rurius a prominent civke on the top of the hill on the 

 side of Heathcote Vail. ;>; \\a , T.u,.. X.Z. Inst., Vol. 



^ iMiitt's of plagioclase 

 ;s„is -01 in length and 

 nidine (?) and augite. 

 nearly but not quite 



