A NEW PROCESS. Auckland.

Otago Witness, Issue 2253, 6 May 1897, Page 18

A NEW PROCESS. Auckland.

The Rev. Joseph Campbell, who recently left New Zsaland fov England with the intention of endeavouring to direct attention to the thermohyporphorie process, of which he is the inventor, returned to this colony by the Mariposa, en route for Sydney. The iw. gentleman was interviewed by a New. Zealand Herald representative as to the results of hi 3 vi.sit to the old country, and in answer to questions Mr Campbell said : "My journey to England has been in every way successful, I am pleased to say. You are doubtless aware that my desire has been to bring to light florae system which would facilitate tho extraction of gold from, the refractory ores of the Hauraki Peninsula, and that the process named has been the result of close and careful investigation. I reached London and found thines in a very depressed slate, but, despite this, I found so many (including numbers of friends in Bhiglind) taking an interest in this important matter that it was decided to form a company — on the distinct understanding, however, that any work undertaken would be carried through under my own personal supervision. On account of t'lis stipulation I shall devote^ another year to the matter, during which time it is intended to erect a yilant at Te Aroha. This will be erected under my own supervision. My hyperphorio process was examined and tested in every possible way by the leading metallurgists of England— those connected with the Royal School of Mines and Royal Mint, for instance— and they recognised the importance of the discovery, accorded me their hearty interest and support, and expressed themselves as more than satisfied with the result. A miniature plant was erected at the Royal Mint, and ihe process subjected to the severest test possible. Ores of the most refractory nature from Australia and South Africa were tried with wonderful success. As one result of the successful nature of the investigations a preliminary company of £25,000 was formed to work' the process. Tt is intended, however, to form a company of from £250,000 to £500,000 to extend operations in all the colonies and to Europe, Asia, &c. In America and Africa two companies will be formed, and already arrangements have been completed in America for the formation of a company of 500,0'0d0l to form subsidiary companies in the United States and elsewhere. I may say that when in America I paid a special visit to the largest mining camp in the world, situated at Cripple Creek. Colorado. There I saw tellurides of gold worth 132d0l per lb, while to see tellurides worth Idol pei- lb was a very common occurrence." iMr Campbell here showed samples containing tellurides of gold (calaverite), said to be worth f u'ly 2dol per lb.] " I visited the ore dumps and frequently found ore worth from sdol to lOdol per lb thrown on one side. It had been found impossible to treat it by any knownprocess, but thethermo-hyperphoric system will treat it at a co-st of about 2dol per ton. So far no known process has treated refractory ores satisfactorily. Some have adopted smelting. This has proved a failure on account of the ore volatilising. Then cyanide and chlorination have also been tried, but in the treatment of refractory ores they have not given the best of results. In British Columbia, where there are masses of ore containing arsenical pyrites, they have been trying the bromo-cyanide process with partial success, but with the hjpeiphoric treatment over 80 per cent, of gold is saved. The cheapness of the system is one of its recommendations. With a complete plant between 100 and 500 tons per day could be treated at a cost of about 5s per ton, including crushing, trsating, and amalgamating."

" And what are your future intentions?"

"Well, I had intended_ remaining in Auckland, taking up my residence in tho Te Aroha district, but communications which I have received render it necessary that I should journey to Sydney for a time. I intend being back here by the end of June, and will then take up my permanent reaideune at Te Aroha. Theplantwhich isto beerected at Te Aioha by .the Mont Ze.rna Gold Mining Company will cost about £6000. It will be capable of putting through from 50 to CO tons per day, but with a very small expenditure it will be apable of putting through 100 tons per day. I

am quite confident that the process will save 95 per cent, of any ore on the Ilauraki Peninsula. I hope to have the plant erected by the end of October. I may, say that during the experiments conducted at the Koyal Mint we had a sample of Australian pyritical ore which no known process could treat. By thehyperphoricprocess (whichconsists of water gas being conducted in closed furnaces to the ore) SO per cent, was extracted with the imperfect plant erected. Another sample (this was from the Transvaal) was also treated by the chlorination process, and 20 per cent, could be saved, but by the hyperphoric process 90 per cent, was extracted, and many other results of a similar nature were obtained. I am quite convinced that the secret of treating telluride ore has been solved, and that the discovery will have a wonderful effect on mining in all parts of the world. In New Zealand, too, tellurides have been come across in many of the mines. I may say, in conclusion, that while at Home I brought myself into touch with leading metallurgical and other scientists', and have secured their cooperation and coidiil help. lam convinced that any rock from the Hauraki Peninsula can how be easily treated, and by securing the co-operation of the leading scientists of Euglaud and elsewhere I hope to help New Zealand mining in many ways."