NORTH AUCKLAND.

New Zealand Herald, Volume LXVII, Issue 20716, 8 November 1930, Page 13

NORTH AUCKLAND.

REMARKABLE COUNTRY.

QUICKSILVER DEPOSITS. OPERATIONS NEAR KAIKOHE. THE EXTRACTION OF MERCURY. '/ OUP. SPECIAL COMMISSIONER. No. TX. Beyond Whangarei lies the most interesting and romantic part of North Auckland, where the peninsula is widest. Ab each corner of it arc great harbours, Kaipara and Hokianga on the west, Whangarei and the Hay of Islands on the east. It is a land of strange contrasts and great promise. Broad swamps alternate with curiously shaped peaks, rich volcanic soils with stretches of barren-looking gum lands.

Its western coast is straight as a ruler; its eastern side carved info all sorts of bays, inlets, coves, headlands and promontories. All kinds of agriculture and horticulture can be and are carried on here, for its climate and its soils enable most of the, best fruits of the earth to flourish and nearly every kind of rrop can be grown. Minerals in infinite variety are to be found. Iron, coal, cinnabar,

silver, manganese, antimony and even gold, while in the northern part is one of the most unusual mines probably in the world, where quicksilver is now being obtained from the vicinity of hot springs. Mercury Minfng Near Kaikohe. One of the first journeys T made from Kaikohe was to visit the works of the Kaikohe Development Company, which lie a few miles from this rising town. This company is, 1 understand, one of the many undertakings-of Imperial Chemicals, Ltd., a great British organisation. The country where the works are situated looks as if it could offer little mining promise, being ordinary gumland lik«

that about Henderson or Swanson, but infinitely more barren looking. Tt was only when we turned off th-» highway along a well-metalled road through the scrub and my companion mentioned that this road had been mad® by the company at is own expense, and that although it taps some thousands of acres of Crown land, neither the Slate nor the County Council had given any assistance, that I realised that anything of importance could exist in this desolatelooking district. When we topped a slight rise and looked down into a shallo-.v natural basin I saw extensive new buildings, with tall structures like poppetheads, and aerial trams which reminded me of some goldmining plants at Waihi or Karangahake. It was not, however,' until the superintendent, Mr. Goodwin, very kindly showed me through the workt that I gained any idea of this unique mine and the manner of its working An Elaborate Plant.

I am not capable of explaining the scientific side of the operations, but I could recognise that the elaborate plant .was admirably designed to deal with large quantities of material in the most economical manner and with the least expenditure of human labour. A steam scoop, working from a tall tower, slides up and down a strong wire cable, dips into tiie hollow wlicre the mineral springs rise, bites into black soil and mud, fills itself with a simple action and slides up the cable with its load and tips it into a hopper. The hopper automatically empties the material into an aerial tram and the laden steel buckets travel in procession to the top of the great building and empty their contents into another hopper, from which the material descends into the interior, of tho works. Here it is dried and then passes into a great steel cylinder, the interior of which is red with heat. It passes slowly through (his cylinder, where the heat volatilises the mercury, and in the form of gas this valuable material is carried into condensers, which reduce it once more to it« normal form. Difficulties Overcome.

The process of obtaining quicksilver from the earth about the Ngawha Spring# as just described gives only a mere indication of skill and thought which must have been applied to bring it into practical operation. The mere handling of great quantities of wet, sticky material, as any miner knows, causes great difficulties, and the work of extraction must have cost Mr. Goodwin and his staff much experiment and thought, because no other mine of this character lias ever before been worked, and therefore there has been no past experience as a guide. That mercury has been won from thi» strange place is undoubted, for I saw a good-sized cauldron half-full of it and had the pleasure of witnessing a solid steel scoop floating on its surface as if it were a cork. Moreover, I was asked to lift one of a row of good-sized cupolas from the floor, and found that I could not move it. except at the risk of a backstrain. ~ No doubt curious peoplo will want to know whether this mine is profitable. This fact is not likely to be made known, •because operations are still to some extent in their initial stage; and. moreover, this is the company's private concern at present. I can only say that a company like this, which lias the. command of the leading experts of the world in this class of mining, is not likely to erect such a largo and expensive plant if there is not some reasonable promise of financial returns.

Origin a Mystery. As to (he quantity of mercury bearing material, if one can judge by surface observation, there s.ecms to be enough to keep this plant going for a long while, and I understand that t here is a prospect of its capacity being largely increased in the near future. One of the things that deeply interested mc was the origin of the quicksilver in this part of New Zealand. It certainly novcr came from anywhere near the surface, for the surrounding country is not mineral-bearing, and at best one can only theorise on the subject. It is, of coarse, possible that its origin may lie in cinnabar deposits in rocks far below the surface and that the hydro-therm.il action of the springs may in some strange chemical process, working for perhaps thousands of years have leached out the valuable mineral and distributed it through acres of grounds. But there is no need to theorise on this remarkable deposit. Wo shall know some time from actual results whether it is going to swell the exports of New Zealand, and in the meantime we must look upon it not only las one of the most remarkable miries in North Auckland, but in the world..