IRONSAND & ORE

New Zealand Times, Volume XLIV, Issue 10288, 24 May 1919, Page 11

IRONSAND & ORE

PRODUCTION OF PSG-IRQPS

OONSIDEKED POSSIBLE BUT NO? ECONOMICAL.

The largest iron ore deposits in New Zealand, stated Mr P. J. Morgan, Government Geologist, at Thursday's sitting of the Industries Committee, aro the limonite of thofgarapara district, and the ironsand <fn and near the coast of Tnrauaki. At Paraparn, the Washbourn block contains at least 22,700.(XX) tons of iron ore, having an iron content of between 45 and 51 per cent. ThoTukurua block, according to Dr,!.-«!.Bell, about 11,000,000 tons of iron oro, most of which is equal in qualitv to that of the 'Washbourn block. 'The Ouaka block, according to a rough estimate by Dr J. M Sell, contains 30,000,000 metrictons (about 29,500,000 English tons). The average iron content, as deduced from numerous analyses of surface samples, is 45 per cent. The Parapara district thus contains at least 63,000,000 tons of iron ore, probably averaging about 45 per cent, of metallic ore. The ore is therefore of medium grade. It has the defect of containing phosphorus in excess of the minimum required in ores from which acid hearth >or converter steel is to be made. It Is, perhaoß, unfortunate that the phosphorus is under l-7th of 1 per cent , because this percentage is-far too small to give the slag made by the basio process any value for agricultural purposes. Probably, when fully developed, tho Parapara deposits will be found to contain a much larger tonnage of iron ore than that stated above. TARANAKT AND OTHER DEPOSITS. »

Tie most extensive deposits of ironsand in New Zealand are near Patoa. According to estimates made by Mr W. Gibson, of the Geological Survey, at least 5,374,000 tons of High-grade sand exist in this locality. In addition there is an enormous amount of lowgrade material that could easily to concentrated', both here and elsewha.-.i. No estimate of the amount of ironsand near New Plymouth has been made. There is much low-grade sand on or near the beach between Motnroa and Urenui. . Taranaki ironsand will probaoly ! make iron and steel of high quality. 'lt has two main drawbacks—<l) its finelv divided condition, and (2) its content of titanium droxide. Exact ; analyses show that the phosphorus | content is somewhat too high for ibe manufacture of steel by the nod hear+h process. ..'»". I Other New Zealand localities for iron ore are Kerr Point and "Waitangi river, North' Auckland : the Raglan-Kawhm •district; Mt. Peel, Nelson; Mt. Rojaj. near Palmerston South; Table 'iill, ; near Milton'; Lake Wakatipu district; and Mt. Oook district (.Westknd. s:de). ' At Kerr Point the deposit of iron cro ; consists of limonite. The ore is scattered over many acrea of ground, but all told is probably not more ihnn 100,QOO~ tons. The iron ore near the herid of the Waitangi river is limonite of excellent quality. The quantity, however, is leas than 100,000 tons. The material-occurs in; small patches, wiGn 'B. total area of about eight acres. The thickness does not exceed four or five feet. The deposit or deposits of iron ore in the Kawhia-Raglan district so far as known are not large. They consist of limonite. Little authentic information concerning the iron ore at Mt. Peel cnv °e obtained. The deposit Is reported to be large, but iivsis doubtful; and, in any case, difficulties of transport render the deposit of no present value. The amount of iron ore 'at Mt. Royal is not known. The material is known to be low grade. The i Table Hill deposit consists of limoni ite. Probably it has' no great extent, i According to Mr S. IK. Cox, haemaI tite occurs in a discontinuous band ex- ; tending from the upper, part of Moke Creek, through Benmore, and thence ''■ in the direction of Mt. Gilbert. A ; six-foot vein occurs at Maori Point,. Shotover river! Large quantities of magnetite are' disseminated through chlorite schist on the Westland side of Mt. Oook. In places it forms beds six Ito eight inches thick. . . i WORK PARAPARA ORE FIRST. | Keplying to questions, the witness ! said that he would try Parapara ore | first for the production of pig-iron. It i eould be produced much more cheaply ! there than from Taranaki ironsand. fie | thought it would be better to bring the ooal or coke to Parapara, because it would take two tons of ore to make one ton. of pig-iron and only. 1 1-7th tons of coke. He did not think, however, that the time had yet arrived When the ore could be worked at a profit. Pig-iron to be produced economically must be produced on a large scale —SOO tons a day—and New Zealand required only 30 tons a day. To make the balance into steel would be a very expensive proposition. He considered that the present demand did not justify the starting of the works. He believed, that, working on a large scale, pigiron could be produced from Parapara ore at from £3 to M, per ton, but it would cost £5 a ton on a small scalo.

Mr Luke: In pre-war days it covlld bo imported at about £4 a ton. Mr Morgan: Scotch pig-iron cost £2 a ton. ' .

To Mr Sidoy: He was quite In ravour of the Government considering the production of pig-iron in NcwZenlnnd. Ho thought it would bo advisablo to obtain an expert from Home for a period of a year or more to report and_ advise on the whole subject * of ironsmelting. To Mr Hornsby: The protection of the Parapara lease expired towards the end of, the year; and, unless the syndicate holding the lease could fulfil the conditions ho thought it would be well, to forfeit the lease. If tho development of iron were left to privato enterprise, the Government would be asked to give a. very heavy subsidy. A development company had asked the Government to guarantee interest on £600,000 for SO years on its Iron works, and he thought that in that case the Government had fnr better build and own the works itself. He thought that the Taranaki ironsand would ultimately be very valuable to the country. At present coke was wastefully produced by driving the gnses into the atmosphere. It would be better to mako the coke in Wellington, where tho gases could be used for power and other purposes.