IRON ORES IN NEW ZEALAND

Dominion, Volume 12, Issue 204, 23 May 1919, Page 10

IRON ORES IN NEW ZEALAND

VALUABLE BUT UNWORKABLE DEPOSITS

FUTURE POSSIBILITIES

Information as to the iron resources of Nevr Zeuland.was given by Mr. P. G. Morgan, Director of Geological Survey, to the Parliamentary Industries Committee yesterday. Mr. Morgan said that the deposits of iron in New Zealand were important, but that thoy could not yet be profitably worked. "The largest iron ore deposits in \ew Zealand," said Jlr. Morgan, "are the hmonito of tho Parapara district, and tho ironsand on and near tho coast of Taranaki.

> At Parapara the 'Wnshbourn Block' contains at least 22,700,000 tons of iron ore, having an iron content between Jo ami 51 per cent, of iron. The Tukurim Block,' according to Dr. J. M. Bell, contains about. 11,000,000 tons of iron ore moat of which is equal in quality to that of 'Washbourn Block.' The 'Onakaka Block,' necordinjr to a rough estimate by Dr. J. M. Bell, contains 30,000,000 metric tons (about 2S/iOO.OBO English tons). The average iron content, as deducted from numerous analyses of surface samples, is 45 per cent. Tho Parapara district thus contains at least /GIt.OOO.OOfI tons of iron ore, probably averaging about 45 per cent of metallic iron. The ore. is therefore of medium grade. It has the defect of containing phosphorus in excess of Hie minimum required in ores from which acid hearth or converter steel is to be made. It is perhaps unfortunate that the phosphorus is under ]-7th of 1 per cent., because this percentage is far ton small to give the shg made by (lie basic process nny vnlnc for agricultural nnrposes Probably, when fully developed, tho Parapara deposits will be found to contain a much larger tonnage of iron ore than that' elated above.

About Ironsand. "The most extensive deposits of irotisand in New Zealand are near Patea. According to estimates made by Mr W Gibson, of the Geological Survey, at least 5,374,000 tons of high-srndo sand exist in this locality. In nddition, there is nn enormous amount of low-grade material that could easily Ije concentrated, both here and elsewhere. No estimate of the amount of irorisnnd near Now Plymouth hns been made. There is much iowgrade sand on or near the beach between Moturoa and Urenui. Tarannki jronsand will probably mnko iron and steel of high quality. It has two main drawbacks: (1) Tts finely divided condition, and (2) its content of titanium dioxide. Exact analyses show that the phosphorus content is somewhat ton high for the manufacture of steel by the acid hearth process. Small Deposits. "Other New Zealand localities for iron ore are Kerr Point and Waitangi River, North Auckland; Raglan-Kawhia district; Mount l'eel, Nelson; Mount Royal, near Palmorstbn South; Table Hill, near- Milton; Lake Wnkntipu district; Mount Conk district (Wesjliiiitl b-ide). .At Kerr Point the deposit of iron ore consists of liiuonite. The oro is scattered over many acres of ground, but nil told , is probably not more than 100,000 tons. Tho iron ore near (he head of the Waitangi River is limonite, of excellent qualify. The quantity, however, is less than 100,000 tons, 'ilio material occurs in small patches, with a total area of about eight acres. Tho thickness docs not exceed four or five feet, Tho deposit or deposit.? of iron ore in tho lOiwiiin-Ilag-lan district no far as known are not lnrge. They consist of limonito. Little authentic information concerning tho iron ore at Mount Peel (Nelson) can be obtained. The deposit is reported to bo largo, but this is doubtful, and in any case difficulties of transport render the deposit of no present value. The amount of iron ore at Mount Royal, near Pnlmerston South, is not known. The material is known to' bo low grade.. The Table Hill deposit consists of limouite Probably it has no great extent.

"According to Mr. S. H. Cox, haematite occurs in a discontinuous band extending from tho upper part of Moko Creel: through Benmore, and Ihenco in the direction of Mount Gilbert. A six-foot vein occurs at Maori Point, Shotover River. Largo quantities of magnetite are disseminated through chlorite schist on tho Westland side of Mount Cook. In places it forms beds, six to eight inches.' thick." No' Commercial Possibility, To Mr.. Luke: In the piercing of the Otira Tunnel little information of geological importance was obtained. Some graphite and a little manganese were found. Of the iron deposits in the country, those at l'arnparn were most valuable, because from them pig iron could be made, though not at low cost. Tho deposits were bigger than anywhere else, find could bo worked more cheaply. It would be , better to take tho toal to Parapara than to take the ore to tho coal centres.

To Mr. Hudson: He could n>it ao'vocate the immediate developing of Parapara. To make.it pnyablo the peduction would have to be at iho :ato of 500 tons of pig iron a day, whereas the needs of the country only amounted to 80 tons a day. Steel might bo made, but 'it would be- yw ycostly steel, he feared. To Mr. Sidey: His estimate o f the cost of production of pig iron at Parapara on a largo scale was at between £3 and £i a ton. On ,->i small .«cale the cost would be about SS a ton. These were less than present importing prices, but a few years ago the price o'f. Scotch • pig iron was about .£2 a ton. He was prepared to say that the Government fjhould consider the development of Parapara, and for this purpose the services of a highly qualified export from England should be engaged. To Mr. Hornsby: He ' thought the Government would ho wise to resume Parapara on the expiry of the present lease, to a syndicate, which lease would expire at the end of the present '/ear. Wilkinson: If tho develop, ment of Parnpara were left to private •enterprise the Government. would bp asked to pay a very large subsidy, and tho Government might as well pay for tho iron works.

To Dr. Newman: He knew no method of smelting the titanifcrous iron ore of Tarannki. Some success liatl been achieved in some parts of the- world with a process, ho believed. He was sure that a process would yet bo discovered which would make valuable the Tnrannki ores, which were of fairly high grade.