Page:Downey•Quartz·Reefs·West·Coast•1928.pdf/24



What are known as the Taipo reefs occur in a belt of country that may be considered the northern extension of the Wilberforce area. The Taipo River has its source immediately north of Mount Harman, and flows in a general east-north-easterly direction for about fourteen miles, when it turns north-westerly till it junctions with the Teremakau River. Most of the known outcrops of quartz occur in the creeks running into it from the western side. Very little prospecting has ever been done in this region, and practically all that is known of its reef-occurrences is contained in Bell and Fraser’s “Geological Survey of the Hokitika Sheet, North Westland Quadrangle” (Bulletin No. 1, New Series), most of the outcrops having in fact been located by members of the party engaged in that survey. It cannot be said that many of the outcrops discovered showed any decided promise, but there was sufficient evidence of gold in some of them to indicate that the area containing them was worthy of further examination. The geologists referred to describe the belt of likely rocks as being about five miles in width, bounded by an artificial line drawn from the north-eastern corner of Turiwhate Survey District, in a direction of south 38° west, to the south-western boundary of Browning’s Pass Survey District. Following the Taipo River down, outcrops were found in Gold Creek, Dunn’s Creek, Freitas Creek, Scotty’s Creek, and Low’s Creek. Careful washing of the decomposed vein stuff, and crushing and panning of freshly broken quartz, served to show that a little gold occurred in most of them, but in only one was what appeared payable quantity of the metal noted. This was in an occurrence in Gold Creek, a small tributary entering the Taipo River well up towards its source. In the bed of the creek, and about seventy-five paces from its mouth, the survey party discovered a bedded reef formation consisting of narrow alternating bands of greywacke and quartz striking north 60° east and dipping at a high angle to the eastward. The formation was exposed for about 3ft. from the foot-wall, but the hanging-wall portion was covered with heavy creek debris, so that the full width-was not ascertained. Along its line the formation seemed to have no continuity to the north, while to the south talus debris covered everything up. The visible portion of the outcrop was only about 6 ft. in length. The quartz bands in the formation only formed a minor proportion of the whole, and were narrow, the widest being about 4 in. The quartz was of a favourable character, showing numerous small angular slaty inclusions and pyrite throughout. One of the quartz bands was highly auriferous, and where it was widest (4 in.) every fragment broken out showed coarse gold, and others of the small quartz bands contained gold in lesser quantity. Samples taken from portions of the formation showing no gold gave on assay 1 dwt. 14 gr. gold per ton, while two other samples from which everything showing gold was selected and discarded gave 1 dwt. 16 gr. and 1 dwt. 6 gr. respectively. An assay of a sample from the rich band yielded at the rate of 5 oz. 3 dwt. 8 gr. gold and 17 dwt. 15 gr. silver. The quartz bands in the formation showed a tendency to widen in a southerly direction below the talus debris, and further investigation of it in that direction seemed warranted.

It may be mentioned that about three years ago a party of prospectors under the direction of Mr. Sidney Fry went into the locality specially to make further investigation of this formation. Owing to the chairs that had been used for crossing some of the streams along the route having been swept away or rendered unsafe, and the old track being badly blocked by