MINING INDUSTRY.

New Zealand Herald, Volume LVI, Issue 17254, 2 September 1919, Page 5

MINING INDUSTRY.

PROSPECTS OF REVIVAL.

REVIEW OF OPERATIONS.

THE UNCERTAIN FUTURE.

The prospects of a mining revival in the Auckland district goldfields are not remote, although there are factors which

at present militate againet any increased activity in the industry on an extensive scale. Some of these hindrances would

be removed were to

undertake- Jhe revision of the present legislation and its accompanying regulations, so as to encourage and foster enterprise which has for too long been discouraged. The outlook would be brighter, moreover, were vigorous efforts made with the aid of the State to unearth new fields in untried and unprospected areas. So far as the future of the industry is concerned, the best prospects of stability are confined to Ohinemuri, in which the three principal bullion-producing concerns are situated, namely, the Waihi -and Waihi Grand Junction mines at Waihi, and the Talisman mine at Karangahake. At Coromandel a resumption of operations in the famous old property, the Old Hauraki, will shortly he undertaken, and a few other propositions in the same district are being worked by syndicates or small companies. At Thames the entire hope of any sort of a revival lies in the direction of fresh discoveries in a new

portion of the field. At Waihi there has„ been no cessation of activity, though developments in the two large mines there have been delayed by the war, and the consequent difficulty in obtaining the necessary machinery for the prosecution of deep sinking. Now that the war is over a renewal of operations to prove the reef systems at . a greater depth will shortly be possible, and the plans of the Waihi Gold Mining /Company in that direction are taking shape. The deepest level at which work is proceeding in the Waihi mine at present is No. 11, 1300 ft below the surface. No. 12 level, 150 ft below that again, has been opened up, but not yet driven on, and the water is standing between the two levels. The policy of the company is to go down and see what is in the deepest levels, and with this object in view the necessary electric pumps, etc., long on order, are expected to be to hand before very long. In the meantime the company continues to produce regular returns, and to pay quarterly dividends. Development of Grand Junction.

In the case of the Waihi Grand Junction mine recent developments have been Oi an encouraging nature, especially as regards the following up of the Mary reef from the company's late boundary into the area hitherto owned by the Waihi Extended Company, but now in the possession of the Grand Junction Company. j With the acquisition of this area the latter company has the reasonable prospect of tracing and working the Waihi reef system out into the flats, which run for a long distance eastward. As to deep sinking, the proposition for the Grand Junction Company is a large one. and up to the present it has not ventured to solve it entirely on its own account. Instead, ! it has regulated its sinking according to the. depth sunk by its neighbour, the Waihi Company, the pumping operations of which have been of considerable assistance. It was announced" recently that the Grand Junction Company intended to resume development work in the western section of its property, on the other side of the Martha Hill. That area comprises what were once three distinct mines, namely, the Waihi West (always owned by the Grand Junction Company), the Waihi Consols, and the Waihi South. The first-named lies at the base of the Martha Hill and there i* a shaft down at a point some 50 yards only from the Waihi Company's boundary on that side. This -shaft was sunk some years ago, on the approximate line of the Welcome lode, to a depth of just under 300 ft. At 160 ft and 270 ft drives were put in on the Welcome which proved to be from 6ft to Bft wide, but not of a payable nature. No work ha? been done in these drives since 1908. i The Waihi Consols shaft was sunk some' 940 ft from the Waihi Company's boundary to a depth of 500 ft. Only barren andesite country was penetrated, so that future operations here must be in the direction of further sinking. The Waihi South Company sunk a borehole about 18 chains south-west of the Waihi West shaft. This went down lsoQft in andesite, indicating that it was in a very deep valley. Here, too, therefore, the problem is a deep sinking one. It is considered in mining circles that this western area will repay a more vigorous development policy, and operations therein will therefore be watched with a great deal of interest. Talisman ia Transitory Stage.

The Talisman mine at Karangahake is at present in a transitory stage, as the '■ visible pay ore reserves are just about ex- i hausted. There are still patches between Nos. 15 and 14 levels, which the manage- . meni is taking out'and crushing. This ore j is about paying working expenses, it i having to be remembered that in this property only fairly high-grade ore pays , to take out. With that knowledge before ! them the directors decided, on the advice ! of the mine superintendent, Mr. H. ' Stansfield, to put down three boreholes from No. 15 level to intersect the reef at between 450 ft and 500 ft below that level. The first borehole, in the Woodstock section of the mine, has been completed. It intersected what is be'ieved to be the main reef in this area, which was proved to be somewhere between Bft and 10ft wide. On j its intersection a very high pressure of water was encountered, and this in itself would indicate a fairly strong body of j ore at that point. The second bore is j going down in what is known as the Bonanza section of the mine, and the chamber for it has been cut almost opposite to the No. 6 winze, -which has always followed down some of the beet ore in the mine. After boring about 147 ft in first-class country the drill entered a country fault whici made boring very difficult, and the management suspended operations until the hole could be protected by a casing. This is now at the mine, and boring operations at this point will be resumed very shortly. The third bore is to go down in the Dubbo section of the property, about 1000 ft further south j in the vicinity of No. 12 winze.

Large Unexplored Areas. In the meantime, a winze, No. 16, is being sunk at a point immediately below No. 16 rise, where a make of good stone was encountered in No. 15 level, going south. On No. 15 level the reef has been carried for 1500 ft, and for almost the whole distance it was a good body of ore and encased in what is generally considered to be good country rock for carrying values. There exists a large area of ground at ' the back of the Talisman area propers and owned by the company, but the future of this unexplored portion of the property will ony be considered after the results of the boring operations are known. The peculiar characteristic of the Talisman mine is that the pay ore has always occurred in zones. These have been divided from each other by barren or almost barren patches, more or less extensive. Should the whole of the three bores now in hand prove the existence of the reefsystem below the present deepest level, it will be an encouragement to the company to continue to open up the mine at a greater depth. Thames and Oorostandel Fields, It is quite unlikely that the Thames deep levels wUI be again explored. The last effort was expensive and fruitless, and the Government is now disposing of the Thames Hauraki pumping plant, by means of which the necessary unwatering was effected. The putting in of the 1000 ft level cost £610,000, and it was then estimated that to unwater the field would absorb £7000 to £8000, while the annual expense of keeping the mines free of water would be £7000. The original five companies who were in the "deep level scheme are now in liquidation, ■except the Waiotahi and the Kuxanui.

The former has sold some of its plant, and it would be quite impossible for any . 1 t ? le companies to go in for a deep sinking proposition again. If mining is once more to be undertaken on a large scale it will have to be through new discoveries. . These can only be made possible under a vigorous prospecting scheme in the untried areas.

There is a more hopeful ton© at Coromandel, owing. to the promised development of the Old Hauraki mine. A new company has been formed which will soon be at work. The intention is "to sink the shaft deeper and explore the lower levels. It was in this property that fabulous returns were won from Legge's reef. Captain Argall, who was the manager of the property in those days, has joined the directorate of the new company, and will take an active part in the future operations.

Smaller Propositions Being Worked.

In other - directions development work is being carried out in various mines with fairly encouraging results as to prospects. To Poke possesses, in Muir's Freehold, a bullion-producing property, the outlook tor which is much liked by experts. There is a compact body of ore, which has been traced for a long distance-, and which has already produced payable returns.

In the Coromandel district the New Waitaia mine, at Kuaotunu, which has yielded small but payable returns in the past, is again being got ready for the resumption of work. At Coromandel itself two or three mines on the Tokatea Hill are being worked in a small way, and there is generally a prospect in this direction of any discovery being a payable proposition, though the runs of gold are usually not extensive, but rather of a " pockety " nature. In the Ohinemuri district the operations of the Rising Sun and Ohinemuri mines are being steadily carried on. At Thames the only mines at work are the Waitangi Consolidated and the Kuranui. both of which are prospecting propositions, while further afield the Golden Belt mine at Neavesville is yielding some gold from time to time.