Iron and Manganese.

In the Mount Torlesse formation there occur some small and irregular lodes, containing carbonate of iron and oxyde of manganese, the latter often forming only a coating on the joints. Nothing has, however hitherto been found in sufficient quantity to be of economic value. Some deposits of clay iron stone are existing in the Clent Hills and some other localities, where beds of conglomerate and shale with impressions of ferns and small and irregular deposits of culm occur. In the lower portion of the Waipara formation, bands of clay iron ore (Spathic iron) are not uncommon, and they are of such thickness that they can be worked with advantage in many places, such for instance as the Malvern Hills, where coal and limestone are within easy reach. An analysis has been made at the Colonial Laboratory, Wellington, of a specimen of clay iron stone (Spathic iron) from the Malvern Hills (9th Annual Report, 1874, page 22).

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Spathic Iron Ore, massive, and striated with bands of the pure carbonate in crystals.

The following is its approximate composition:
	per cent.
Protoxide of Iron	51.2
Manganese Oxide	0.8
Alumina	1.8
Lime	0.3
Magnesia	0.4
Carbonic Acid with a little Phosphorus and Sulphur	31.2
Water	0.7
Silica	13.6
	100.00

Another form of iron ore is also not uncommon in the lower portion of the Canterbury plains. This is bog iron ore (limonite). It occurs there as a modern marsh deposit. It is, however, of inferior value. In Westland, clay iron stone has been observed on both sides of the Paringa river near its mouth, and in the Grey district. On the northern side of the Paringa, in the Bluff, a small lode of hematite occurs. In course of time there will doubtless be an iron industry of some importance in connection with the Grey coal measures, when once the difierent beds of clay iron stone have been fully traced, and labour is more easily obtainable for metallurgical industries.