360 Transactions. — Geology. 



into the other. Graphite-schists, sometimes 13ft. thick, occur 

 in the lower part of the Wanaka series, at the Carrick Eanges ; 

 and chlorite-schists, also belonging to the Wanaka series, are 

 found near Queenstown. 



The Mica-schists of the SJiotover River (Wanaka series), 

 near Queenstown, are distinctly foliated with quartz and mica, 

 and break readily along the plane of foliation. The foliaa often 

 have parallel sides and extend far, but occasionally they are 

 lenticular. The broader quartz folias are always lenticular in 

 shape. The quartz is white and milky, being filled with in- 

 numerable gas-pores, arranged in bands, which are oblique to 

 the plane of foliation. There are no liquid cavities in the 

 quartz, but many of the gas-pores are irregular in shape, and 

 look as if they had at one time been filled with liquid. In 

 these cases the long axis of the cavity lies in the direction of 

 the band. The quartz elements are dovetailed grains, from 

 0'004in, to 0-014in. in diameter, and occasionally they show 

 undulose extinction. In some specimens there are patches of 

 amorphous, isotropic quartz. The micaceous layers are dark- 

 grey and glittering to the naked eye. The microscope shows 

 small flakes of muscovite, from 0-014in. to 0-022in. in length, 

 oriented to the plane of foliation. Part of the muscovite is 

 altered to a green mica with undulose extinction and no axial 

 interference figure. A colourless mineral, apparently zoisite, 

 is very abundant in grains and in jointed columns ; and a fine 

 dust of secondary magnetite is sometimes present, scattered in 

 clouds drawn out in the plane of foliation. 



At Clyde the mica-schists differ from those of the Shotover 

 in the absence of the bands of gas-pores from the quartz, much 

 of which is amorphous. 



The Phyllites of Kingston (Kakanui series) are composed of 

 elements uneven in size, but mostly smaller than those of the 

 mica-schists. They also occasionally contain patches of a 

 fine aggregate, which is probably part of the original rock, as 

 well as broken grains of feldspar. The mica is brownish-yellow, 

 not dichroic, and with low polarisation colours. It is probably 

 muscovite, but the scales are too small to examine with con- 

 vergent polarised light. Zoisite is present as in the mica- 

 schists, which latter differ from the phyllites chiefly in having 

 undergone more vertical segregation as well as more altera- 

 tion. 



The Chlorite-schists of Queenstouni are formed of much 

 larger elements than the mica-schists, and they also contain 

 small quantities of feldspar. The quartz has large gas-cavities, 

 but no bands of gas-pores. The chlorite is in bluish-green 

 flakes, which are either isotropic or else have dull polarisation 

 colours. It is associated with abundant grains of yellow 

 epidote, or pistacite, and crystals of secondary magnetite are 



