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pany, in the Southern District, which have been obtained by a practical working-test as a result of treating 2,250,000 cubic yards of material, the average depth of which was 45 ft., for a return of £22,164, being at the rate of 2"363 d. per cubic yard. The cost of mining was 1 - 75d. per cubic yard, which includes depreciation on plant; the net profit per cubic yard was therefore 0 - 61 d. In this case it has only taken 0 - 88 of a grain of gold per cubic yard to pay expenses. The two elevators which were employed averaged each 69 cubic yards per hour, working 300 days each year. The above figures may be of service as showing an extensive working-test. During 1906 the average cost in the Southern District was about lfd. per cubic yard, and on the West Coast about 2d. At the present time there are in active operation forty-four hydraulic-sluicing and elevating plants and forty-eight hydraulic-sluicing plants, all the property of registered companies, and it is probable that these numbers will be increased during the current year. In addition to the above, a large number of plants are privately owned, and the returns from these are not obtainable. The amount of ground-sluicing in New Zealand is insignificant. The only black-sanding or " beachcombing " in the Southern District is at Orepuki, where twelve men are intermittently employed. On the West Coast a decrease of £18,709 in the production of alluvial gold by registered companies has to be recorded, the total production during 1906 being £86,082. There are at work fifteen sluicing plants and three hydraulic-sluicing and elevating plants. The black-sanding or "beach-combing" in the Charleston district has given profitable returns, one group of fourteen men obtaining £800 in nine days. This kind of mining, however, is very uncertain, depending as it does on the tides and elements, for after storms the best returns are obtained. Alluvial mining in the immediate locality of the once famous diggings of Hokitika and Kumara is dormant, but at Ross a movement is on foot for the purpose of draining and reopening the mines at Ross Flat, which field, formerly known as the Totara Diggings, was first rushed in 1865, and produced large returns from the shallow workings, and later from a shaft sunk by Mr. Cassius, 300 ft. in depth, until in 1872 the accidental tapping of old workings flooded the deeper levels. In 1882 operations were recommenced, but in 1887 the workings were again inundated by the same cause. A shaft sunk by the late Ross United Company to a depth of 392 ft. passed through eight separate auriferous layers and never reached bed-rock. That the ground is very rich has been proved beyond all question, but the working of the same and the winning of this hidden treasure will require skilled management and adequate working-capital. In such a proposition as the reopening of these mines the employment of insufficient capital will spell disaster, for it is impossible to form a correct estimate on the data available of the quantity of water which will be encountered. The late Mr. T. J. Waters, M.A.1.M.E., estimated that pumps capable of discharging 1,900 gallons per minute would suffice, and other engineers in later reports have accepted these figures. This estimate was based upon th rainfall over a given area of 1,000 acres, but is mere conjecture V. MINERALS OTHER HAN GOLD. Copper. The high market price ruling for the metal copper has caused increased attention to be given to the cupriferous deposits of New Zealand, and several mines which have been closed down for a considerable period have been reopened. At Pupuke, near Whangaroa Harbour, three syndicates are engaged prospecting ; but although nodules of chalcopyrite have been found in a much-broken lodelike formation, the results obtained hitherto are far from payable. The old Maharahara Mine, near Woodville, has again been reopened, and a company are obtaining a parcel of ore for shipment. A large siliceous hasmatite lode containing chalcopyrite, and bornite in small shoots is being developed by two tunnels in the slopes of the Ruahine Ranges, but as yet there is not sufficient work done upon which to base an estimate of this property. The Maoriland Copper Company, near Nelson, are reopening the old Champion Mine and the surrounding properties, which have now lain dormant for so many years. A shipment of 500 bags of ore has been recently made from this property. With improved methods and an increased market price obtainable these properties may have a more promising future. During 1906 the discovery of a promising copper-field was made by Messrs. J. and R. Johnson at Mount Radiant, which lies at the head-waters of the Mokihinui and Little Wanganui Rivers, a distance of about twelve miles south-east of the Port of Karamea. The cupriferous veins, which occur in a grey porphyritic granite, have a general north-east and south-west trend, and have been traced for several miles. The outcrops expose strong quartz and feldspar veins, the mineral contents of which are copper, in the form chiefly of chalcopyrite, also molybdenite, and iron-pyrites, the latter carrying small quantities of gold and silver. Insufficient work has been done to pronounce upon the width of the veins or of their " economic possibilities," as no importance should be attached to the results of a fire assay from a picked specimen of outcrop ore, and as yet no tests in bulk have been made ; but