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contract has been let for the construction of a pack-track, and work is now proceeding. Recently production of mica has become a matter of urgency owing to failure of overseas supply and to important war orders for radio equipment still remaining unfulfilled. To meet this situation the radiomanufacturing company took over the claims under tribute agreement. It is of interest that commercial mica has recently been located at much lower elevations with correspondingly more favourable working conditions. Talc—A small production of talc (62 tons) is recorded this year from the Upper Takaka district, Nelson but the deposits proved too small and irregular for continued production. The occurrence of talc is reported from many localities in the South Island, but so far no deposit of suitable grade has been opened up that is capable of sustained production. Bentonite.- -While production for 1943 showed a decrease from 1942, there are indications of an increased demand overseas for this mineral. Phosphate.—A considerable amount of prospecting-work was carried out upon the Clarendon phosphate deposits during the year, two of the Mines Department's diamond drills being continually encaged thereon. One drill, on behalf of the Department of Agriculture, was engaged m exploring the phosphatic sandstone, and as a result of the drilling programme a quarry has been opened up m the Kapiti Block, a grinding plant installed, and finely ground phosphatic material prepared for use m fertilizers. In 1943, 6,070 tons were produced. Efforts to prove up other blocks of similar tonnage to justify quarrying operations were not so successful and the drilling programme has now been abandoned. A considerable amount of testingwork was carried out at the Thames School of Mines upon this material, and it was found that the phosphatic contents could be doubled by concentration by flotation, but unfortunately the tonnage as yet available is not sufficient to warrant erection of a treatment plant or to pursue the matter further. The other drill has been working on behalf of the British Phosphate Commission in exploring the medium-grade horizon that was extensively worked in the past. As a result of this work, stripping operations have been undertaken, and phosphate rock suitable for use in the manufacture of superphosphate has been obtained. Unfortunately, reserves of this material are limited, and as much of it required extensive stripping operations, prospecting-work in this area has now also been abandoned. Of this material, 3,171 tons was obtained, and, in all, some 9,241 tons of phosphate-bearing rock was produced from Clarendon during the current year. Serpentine— The function of this mineral in eking out our diminished supplies of phosphate is of increasing importance, and during the year some 59,445 tons were mined from deposits m North Auckland and 2,200 tons from a deposit at Mossburn. Prospecting-work in North Auckland was continued and a sufficient tonnage of mineral proved to assure a continued supply for the current year. Maqnesite. —Some 171 tons of magnesite were procured from the deposits in the Upper Takaka district and finely ground for use as a fertilizer in the tobacco industry. Dolomite had been previously used for this purpose. Dolomite— Some 3,571 tons of this material were procured from the deposits at Mount Burnett and shipped to Huntly, where it is used in the preparation of basic-slag fertilizer. Limestone.—A record production of 752,603 tons of limestone for agricultural purposes is recorded for 1943. STATE SCHEELITE-MINES In February, 1942, in response to an urgent appeal from the Imperial authorities to increase the production of scheelite, it was decided that the Mines Department should undertake development work in the Glenorchy field. An arrangement was accordingly made whereby the Mines Department took over the Mount Judah and Paradise Mines, of the Glenorchy Scheelite Co., Ltd., and these have been actively operated for the past two years. For a commencement, considerable difficulties had to be overcome, owing to the relative isolation of the district, in recruiting labour, providing housing accommodation, and equipping the mines. However, considerable progress has now been made and an extensive development programme carried out some 2,000 ft. of development work, comprising driving, crosscutting, rising, and win zing, having been completed at each mine, while, in addition, old workings were repaired to allow of a systematic investigation of the mines. Incidental to the development programme some scheelite was produced, while early opportunity was taken to stope ore revealed by development. From these operations 9 tons 3 cwt of scheelite concentrates were produced from the Glenorchy Mine and 6 tons 11 cwt. from the Paradise Mine in 1942, while 25 tons 8 cwt. and 11 tons 16 cwt. were produced from the Glenorchy and I aradise Mines respectively in 1943. Development work has, on the whole, been disappointing, and with considerable improvement in the tungsten supply position further development work has been suspended on the advice of the Imperial authorities. Opportunity, however, is now being taken to extract ore that can be economically produced at the present price level, and up till the end of August of this year 32 tons of concentrates have been produced, approximately half coming from each mine. 2—C. 2.
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