(8) Iron.

Ores.—The ores of iron occurring in New Zealand are both numerous and abundant, and have been divided by Sir James Hector into (1) granular, and (2) massive.

The first-named variety, that is ironsand, is very widely distributed in the colony, but the littoral deposits of the west coasts of both islands are the most remarkable; and at Taranaki the shore-line between high and low water-marks is, for great distances, composed almost entirely of this material. At the Manukau Heads also a similar formation occurs. The iron contained in this sand is present in the form of magnetite, h æmatite, or as titaniferous oxide. The magnetite is derived principally from acidic rocks, such as the granites of the South Island and the trachytes of the North; while the h æ matites or specular ores are derived from the page 51 metamorphic schists, and the titanic oxides from the diorites and basaltic rocks.

The analyses of ironsand which have been made, give from 70 per cent. of iron; and it is a noteworthy fact that most of the sands from the South Island are auriferous.

The next four samples belong to the hydrous ores, of which—

(a)	Is a bog ore, somewhat inferior in quality, as it contains much sulphur, 13.2 per cent, of water, and 13.83 per cent, of siliceous impurities.
(b)	Is a brown ore, from the Tertiary coal-formation of Raglan, near Auckland, and is found in the form of balls or concretionary masses in the coal shales. The following is a detailed analysis:— Per Cent. Sesquixide of iron 72.69 Oxide of manganese .56 Alumina 1.16 Lime .27 Magnesia .69 Phosphoric acid .70 Sulphide of iron traces. Siliceous matter 6.30 Water hygroscopic 4.61 Water constitutional 13.02 100.00 page 52
(c)	Is a sample of the great Parapara limonitic deposit, which occurs in enormous quantities on the surface of the ground near Collingwood, Nelson, It is the hydrated ferric oxide, having the formula 2 Fe2O3, H2O, and contains when pure 59.89 per cent, of iron, At this place it is found massive, earthy, botryoidal, mammillary, and concretionary, and covers the earth in large dark brown masses, sometimes of many tons in weight. On breaking these lumps there is frequently disclosed a kernel of undecomposed sulphide of iron; and Mr. Cox's opinion is that the deposit is the oxidized cap of a large pyritous lode. The writer has traced this deposit for 2,772 yards within the original lease, and is of opinion that it extends to the Onakaka Creek, a further distance of more than a mile. Interspersed among it are waterworn quartz-pebbles, which would necessitate hand-picking. A sample gave:— Per Cent. Sesquioxide of iron 62.68 Manganese traces. Lime .61 Magnesia traces. Siliceous matter 23.47 Water 13.24 100.00

The situation is admirably adapted for the site of an iron-smelting plant. Close to the limonite is a deposit of nearly pure crystalline marble, and 5 miles away is the Collingwood coal-mine, yielding some of the best fuel in the colony. Facilities exist for the formation of a well-sheltered deep-water wharf.

Another deposit of a similar nature has been found at Mount Peel, Nelson.

This occurs with coal-scams which, though somewhat thin, are of excellent quality, and close to the mine is abundance of hue limestone.

Spathic ores of great purity have been found near Ashburton, Canterbury, at Foote's coal-mine, near the Miranda Redoubt (Auckland), and at Jenkins' coal-mine, close to Nelson.

In addition to these commercially valuable ores the following, which are only mineralogically interesting, are known:—

Siderite (FeCO₃) is mentioned as occurring in cavities of the contorted schists of Otago, and also at the Clutha, but the writer is of opinion that it must exist in considerable mass at Hindon, near Dunedin, as a specimen from a vein, which the proprietors were working as quartz for gold, was found to consist of pure carbonate of iron.

Iron pyrites is exceedingly common, and is chiefly interesting, as usually containing gold, and being associated with valuable sulphides.

Marcasite occurs among the brown coals. Pyrrhotine was discovered by Mr. Cox in 1876, near Mount Cook, and has been found in various other places.

Melanterite has already been mentioned as occurring in the goldmines, and is also found in the collieries,

Manufacture of Iron.—Several attempts have been made to utilize these deposits of iron ore, the first being about 1874, when the Parapara Iron and Coal Company, Limited, expended £10,000, partly on the coal-mine partly on cottages and a wharf, and partly on the foundation of a page 54 blast-furnace. Their capital was, however, insufficient, and they went into liquidation without smelting any iron. Lately some 300 tons of the Parapara h æmatite has been sent to Auckland to be experimented on at the Onehunga Ironworks.

The granular ores of Auckland have several times induced capitalists to invest money in their manufacture, and many patents have been taken out for the purpose, but without avail. It is necessary to mix the ore with some cementing material, and for this purpose the scoria or volcanic slag, which abounds in the neighbourhood of Auckland, was at one time tried, but the result was unsatisfactory. The last company went into liquidation, and the plant was bought in by the mortgagees, who employed it in working up all the scrap they could get in New Zealand, and subsequently old iron rails bought In Queensland, which were re-rolled into pit rails. Some pig iron was made of iron ore brought from Whangarei (some 70 miles north of Auckland) by sea, after being carted 1 mile and railed 8 miles to port; it was then carried by sea to Auckland, and by railway 7 miles to the works at Onehunga. The limestone was brought from Kuiti on the Waikato River, 125 miles away, It could hardly be expected that this would pay, and, as stated, Parapara ore was nest tried, smelted with coke brought from West port and Greymouth.^* The Government of New Zealand has not been backward in encouragement to the iron industry. In 1879, full particulars of the natural resources of the colony in iron, coal, and limestone, were circulated in Europe and America, and tenders were called for the supply of 100,000 tons of steel rails, manufactured within the colony from New Zealand ores. No offers were received.

In 1886, a bonus of £1,000 was awaiting the successful manufacturers of 200 tons of wrought-iron blooms, and the New Zealand Iron and Steel Company, then at work at Onehunga, was intending to apply for it. In February, 1892, the government made a further offer of a bonus of £1 per ton for the first 500 tons of pig-iron of marketable quality manufactured from ironsand in the colony, all material, fuel, and fluxes, to be the produce of New Zealand.

It is worthy of mention that the hæmatites found at Thames (Auckland) and at Parapara, are largely used in the manufacture of paint.

Exports.—The official returns give the total quantity of hæmatite ore exported to the end of 1890, as 52½ tons, valued at £225, but Sir Jas. Hector's valuable "Handbook of New Zealand" for 1886, states that up to the end of 1885, the iron ore exported amounted to 209½ tons, valued at £1,066.

It will be acknowledged that iron ores of varying and sometimes excellent quality are widely distributed in New Zealand, and that first-class fuels and fluxes are often found in juxtaposition, but the scattered population of the colony and the cost of transport have militated against the manufacture. Wages also are very high, and prices in England and freights to the colony are very low. It appears to the writer that some of these factors must undergo a change before the industry can be started on a large scale with any certainty of proving remunerative. At the same time it is consolatory for those who have the welfare of the colony at heart to know that there are within its boundaries the elements of a successful metallurgical industry.