Auckland Institute. 403 



length, and from each, what I presume to be an average specimen of the rock 

 passed through, has been sent, together with samples of the reefs cut. 



" \st Section on West Side. — A dark, very compact base, containing 

 tabular crystals of felspar, and grains of a red mineral not determined. The 

 structure is only visible in the heart of the fragments, which are weathered on. 

 the outside, of a mottled green, and dirty from earth. 



" 2nd Section. — Soft rock of a light buff colour, mottled as if formed by 

 the decomposition of a felspathic paste, containing an imperfectly crystallized 

 mineral. 



" 3rd Section. — Fine-grained breccia containing rolled pebbles of the 

 tufanite rock in the 4th and 5th sections, and iron pyrites in small quantity ; 

 evidently a rock that has been decomposed. 



" 4:th Section. — Compact white paste, speckled with blue spots, that have 

 no defined shape, and containing much pyrites. 



" 5th Section. — Sharp granular rock of light grey colour, containing large 

 quantities of pyrites in brilliant crystals and grains. This is the characteristic 

 tufanite of the Thames Gold Fields. 



" In this rock the first quartz vein was met with, lying very flat, the dip 

 being 22° to south-south-east. Its thickness on the plan is stated to be 

 1 foot 6 inches, and its yield 19 dwts. per ton. 



" The sample sent of the quartz from this vein showed distinct traces of 

 gold, but the quantity was too small to be determined. 



" 6th Section, — Dark coloured, compact, heavy rock, containing much 

 carbonate of lime and pyrites. 



" This section is cut through at 560 feet by a quartz vein 6 inches thick, 

 running north and south, with an easterly dip of 25°. The quartz is stated to 

 yield 6 ozs. 10 dwts., but the sample received only gave traces of gold. After 

 a short interval there is a second vein, 1 foot thick, with nearly the same dip, 

 resting on a dyke said to be diorite, but no sample seems to have been sent. 

 The vein-stone is calcspar, with druses lined with crystals of arragonite, and 

 only containing small threads of quartz. 



" 1th Section. — Light coloured, calcareous, and pyritous rock. This is cut 

 by a quartz vein 6 feet thick, and nearly flat, or with a slight underlay of 

 one in twenty to east. The quartz is crystalline, and the sample sent gave at 

 the I'ate of 25 grains per ton of gold. 



" In the 8th section, at 720 feet, a small vein of similar size, and under- 

 lying, was cut, the sample of which ouly gave traces of gold. It is noticed 

 that on cutting this vein a heavy flow of water was met. 



" The rock where the tunnel had reached to from the west side, in June, 

 was compact, granular, and of a dark grey colour, charged with pyrites, and 

 only feebly calcareous. 



