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Scheelite. —The equivalent of 25 tons of scheelite concentrates averaging 65 per cent. W0 3 were produced in 1948, 19 tons coming from the Glenorchy district and 6 tons from Macrae's Flat. This is in keeping with the production level of late years, 22 tons being produced in 1947, 27 tons in 1946, and 34 tons in 1945, but a marked decline from production during the wartime years, when a peak production of 145 tons was achieved in 1944. The low level of production is due mainly to exhaustion of ore and not to the price level, which has remained at a reasonably satisfactory rate. Actually over half of the Glenorchy production was due to the efforts of one party. It is, however, possible that with continued development other parties will locate good patches of ore and that production will be increased. Manganese-ore. —A shipment of 489 tons of manganese-ore was made to Australia from Maning's Mine, Otau, Clevedon, and later in the year 36 tons of ore were sold locally, making the production for the year 525 tons in all. Arrangements have now been made whereby all the ore produced from this mine will be sold to local users and the difficulties in the past of securing shipping space will be obviated. Iron-ore. —From deposits in North Auckland and at Onekaka a total of 4,776 tons of iron-ore were produced for use in gas-purification and in the manufacture of cement and stock-licks. Seeing that the gas industry has now to depend upon New Zealand coals with a higher sulphur content, the production of iron-ore for gas-purification is of considerable importance. A modern electric furnace is now being installed at Onekaka and large-scale experiments are to be made in the smelting of concentrates obtained from Taranaki ironsands by the use of spiral concentrators. Antimony-ore. —After some years, the export of antimony-ore was resumed by the shipment of 9 tons of ore, valued at £268, from the Mount Stokes antimony-mine, in the Nenthorne Survey District. Prospecting operations for antimony-ore in the Bannockburn district have now been suspended owing to disappointing results. Arsenic. —Eight tons of arsenic were recovered as a by-product from the roasting of gold-ores at the treatment plant of the Blackwater Gold-mine and were disposed of locally. Copper-ore. —There was no further activity during 1948 at the copper-mine at North Auckland, but during the present year a small parcel of ore has been roasted to reduce sulphur content so that danger from heating while in transit can be overcome. A small parcel of this material has recently been shipped to the smelter in Australia, and it is possible that further shipments will be made. Lead-ore. —The high price being obtained for lead has directed attention to leadores. A little preliminary work has been done at Te Aroha, but prospecting-work has had to be postponed until conditions under which such work is to be carried out could be framed to the satisfaction of the Health Department so that danger to the pollution of the local water-supply could be avoided. At the present time Sylvia Mines Consolidated, Ltd., are crushing ore obtained from the driving of No. 6 Level and concentrates are being obtained which will be shipped to Australia for treatment. The results of this test will give information as to the percentage of base metals contained in the ore that are recoverable by modern methods of concentration and indicate whether mining for base metals can be carried out on an economic basis. Bentonite. —Of a value of £4,462, 624 tons of bentonite were, produced during 1948, as against 215 tons, valued at £1,049, in 1947. All of this amount was produced from the Porangahau district, the major producer being New Zealand Bentonite (Porangahau), Ltd., the pioneer of bentonite in New Zealand. Another company has recently been formed to open up bentonite deposits in the Gisborne district. Although New Zealand bentonite is not strictly comparable with the best grade American type, a good market within its limitations exists overseas for New Zealand bentonite and production and export are capable of considerable expansion. It has in consequence been disturbing to find that inferior material has recently been marketed overseas as New Zealand

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