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96 any rate, the The vein thus appears to occupy the limbs of a syncline; but further development is required to test whether the other limb exists, and whether it carries ore. Owing to the great confusion of strike and dip of the slate I was unable to find evidence of a synclinal arrangement from sur- face observations. The flattening observed may, indeed, be only a local phenomenon, or an irregularity in the course of the vein. evidence in favour of a syncline is not yet conclusive.

In the development of this mine the diamond drill has played a con- siderable part, sometines with much success. Much care has, however, been found ncccssary in interpreting its indications. Thus, in rcius of this interrupted type a bore may be put in and may miss a block altogether.

Again, it may pass through a block at such an angle as to give a very exaggerated idea of its thickness. bore was put down from a point near the shaft-chamber in No. 11 level for a depth of 1,000 ft., or 2,500 ft. below the surface: po pranising indications were found, but the bore is interesting as being the greatest depth reached in a New Zealand mine. The results of other bores made have given no indication of the existence of a synclinal vein.

The deeper levels of the mine, as of all others in the district. are con- spicuously dry and dusty, except for surface-drainage in the vicinity of the shaft.

(4.) Rainy Creek or Merrijigs Group.

The Rainy Creek gronp, particularly the Inkerman, is noted for the large size and low value of its quartz blocks. One block in the Inkerman Teached a width of 130 ft., but averaged less than 2! (wt. to the ton. The strike of the vein is north-east, and it dips steeply to the south-cast. It contained several large blocks, the Big Blow, the Antimony Block, and the Balaclava Block-- which all showed a slight pitch to the north-cast along the strike. Antimony-ore is common in the Inkerman and in adjacent claims.

The zone of reefs in this part of the district follows an irregular north- and-south line, with frequent divergences and irregularities in strike and dip. Of the others, the Al and Golden Lead were worked for some time, but returns were never encouraging, and mining at Merrijigs is now at a standstill.

(5.) Big River Group.

New Big River.---This lies near the head of the Big River, about twenty miles south of Rceflon. It strikes north and south, and the main block or scries of blocks pitches to the north. Fig. 13 shows the dis- position of quartz in the rein. Blackwater. This is a narrow type of vein. It strikes north and sonth, and dips to the west at about 70%. The direction of dip of the quartz blocks las not yet been definitely ascertained, as the mine is only being de- 9001

veloped. The gokl is free, evenly

Fic. 13.-SECTION. Bu VEIN. distributed, and often coarse. There are frequent blocks of stone, mostly of uniform value, but a few patchy. The blocks have an S. No.21 No.6