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Unfortunately, there is nothing to show what parts of the mines these samples or specimens came from; but, as the reef in the Enterprise had been opened at the time down to No. 3 level, the presumption is that they were taken from all parts of the workings. It is highly probable, however, that the greater number of them, particularly those containing good values, came from the upper or oxidized zone.
In view of the values shown, especially in the samples from the Enterprise Mine, it may be thought that the field did not get as thorough a try-out as it deserved. The poor recoveries obtained in the batteries is accounted for by the fact that bismuth was present in the ore, and this had the effect of sickening the mercury, making the ordinary battery treatment useless for saving the gold. The close association of the gold with the pyrites also brought about conditions tending to cause serious loss of gold, the decomposition of the sulphides and arsenides of iron finding its way to the plates, and also sickening the mercury. If the difficulty of saving the gold was, however, the only one to be overcome it is quite possible that modern metallurgical science could conquer it; but the fact is that insufficient sampling of the deposits was carried out, and insufficient practical testing of the ore done, to definitely determine what the actual values in the lodes were. Park, who visited the field in the early part of 1888, pointed out (Reps. Geol. Expl., 1887–88, p. 87) that careful tests should be made of large samples of the stone to ascertain if it contained payable gold, and that steps should afterwards be taken, by actual experiment, to find out the process best suited to extract the gold. He further suggested that, instead of the companies wasting their capital in individual efforts, they should unite their resources and thoroughly test the claim offering the best prospects and greatest facilities for working. These suggestions were not acted on by the claimholders, consequently some doubt remains as to the real values, but the probability is largely that on the whole the deposits would not have been found to be rich enough in gold to pay for working.
Even had the values been actually much better than those recovered, there was a further obstacle to the success of the field in the lack of continuity in the reefs. Most of the stone found was practically on the surface, and in all the deposits it was much broken. There can be no doubt all of it was faulted from its original position, and, as the whole area had been extremely badly disturbed, the probability is that further investigation would not reveal in situ the ore-bodies from which the stone was derived, but would show that, in fact, no bodies of any extent would be found in any part of it.
BULLER COUNTY.
In Buller County auriferous reefs were located in at least three areas—Lyell Creek, Mokihinui River, and Waimangaroa—from each of which considerable quantities of gold were won.
Lyell Creek Reefs.—The reefs discovered in this locality were the most important found in the county. Alluvial gold was first discovered at the Lyell as early as 1862, but it was not until about 1870 that quartz-mining began there. The United Alpine Company, registered in 1874, was the first to be formed to work the reefs, and it started operations on a reef discovered on a high ridge on the south side of Lyell Creek, about two and a half miles up that stream from its confluence with the Buller River, where it succeeded in opening up what proved to be one of the most profitable mines in the Nelson Province, and one which continued to yield fair quantities
