QUICKSILVER IN NEW ZEALAND.

Otago Witness, Issue 3523, 20 September 1921, Page 55

QUICKSILVER IN NEW ZEALAND.

At a meeting of iiie Otago Institute held on the 13th inst. Professor Waters gave a lecture on “Quicksilver, and Reference to its Occurrence in New Zealand.” He traced at some length the history cf the metal and its uses, and then proceeded to deal with discoveries in Now Zealand. Cinnabar was known to exist here as early as 1875. It was worked on a small scale at Waipori from 1902 to 1905. and later was found at Nevis. Unfortunately, as in the case of other metals in the Dominion, it only occurred here and there, and the ore was not a payable proposition. Later a discovery was made in the Thames district, where the ore was worked in 1899, amt again from 1905 to 1910. Various companies were connected with the Karnngahape district, and in 1910 £ISOO worth of mercury was produced. There was no evidence, however, of any further production there. To-day a considerable plant was at work at Puhipuki, in the Bay of Islands County, on Mount Mitchell, 1500 ft above sea- level. Originally the district was forc-st-clad, but to-day the timber had gone, and the operations were handicapped by the fac-t that not only was timber for mining purposes difficult to get, but firewood also, the district was high up and inconvenient, and the conditions were not favourable to industry. The company, however, had been favoured by the fact that its operations had extended through the war period, and mercury had been i,n great demand owing to its value as a detonating substance, being greatly used. The mine was stalled in 1917, and up to the end of 1529 it had produced 31,4211 b of quicksilver from 1442 tons of ore —about 1 per c-ent. That was a good percentage for mercury. In America they were pleased to get from ito per cent), and 1 per cent, was considered good; but in Spain the percentage ran up to' 10. so that others were somewhat out of it. Professor Waters produced samples of the Puhipuki ore and that from the other districts he had mentioned. He also handed round photographs of the mine and plant, and explained the method of breaking the ore, ttie principle being to heat it with some metal showing a greater affinity for sulphur than mercury itself possessed. The method pursued at Puhipuki was not the best, but it was simple and effective. The lecturer explained other methods of treatment, and carried out one experiment showing how the mercury could be dissociated from the sulphui in a retort and collected on gold. Before concluding Professor Waters dealt with the uses of mercury, particularly In regard to scientific appliances, gold mining, and medicine. By treating it. with nitric acid and alcohol it became a very powerful detonator, and, as he had said, was much in demand during the war. It amalgamated wonderfully with other metals, and in this regard would be familiar to many from its use in amalgam stoppings in the dental parlours. With regard lo the market value of qui.-k----silvpr. Professor Waters said that Rothschilds practically controlled the world’s supply, and consequently ihe price, their agreement with Spain having been renewed and extended to Italy and Austria, greatly to the dissatisfaction of the Americans. He did not. think it would greatly matter to New Zealand, as there was no prospect at present that any considerable quantities ooulfi be produced here. Several questions wore asked, and a heartv vote of thanks was accorded to the lecturer.