C—3a

14

Percolation-plant: This plant will consist of thirty or more tanks, each capable of holding a charge, according to their size, of from 6to 20 tons of finely-pulverised ore. The bottoms of these tanks will be covered with a sand-and-gravel filter. The method of treatment is roughly as follows : The finely-pulverised ore is trucked from the store-hoppers and tipped into the tanks. A dilute cyanide solution is run on to the top, and allowed or assisted to percolate through the body of the ore. As fast as it percolates it is carried away from underneath the filters on the bottoms of the tanks by means of iron pipes, and allowed to run through a series of boxes filled with zinc turnings. The cyanide in solution having a much stronger affinity for gold and silver than the baser metals, dissolves these precious metals in its course through the ore, and again deposits them in the form of a black slime on to the zinc turnings. This bullion, in the form of black slime, is easily collected and melted down into bars. Treatment by percolation requires no power and little labour. Agitation-plant: This plant will consist of twelve or sixteen wooden tubs fitted with revolving paddles, and capable of holding a charge of three tons of ore each; also three filter-presses, with force-pumps connected, for filtering ore after treatment. This method of treatment is simply agitating the ore and cyanide solution together in tubs or other vessels by means of revolvingpaddles or otherwise, until the gold and silver is dissolved. The solution is then filtered, and the bullion deposited on the zinc turnings as already described. For some time operations have been delayed at the present plant through the bursting of the dam, but since repairs have been made and crushing resumed, they have crushed and treated 240 tons of Crown ore by the McArthur-Forrest process, and recovered 92 per cent of the average value. Adeline Amalgamated Mine has been worked by tributers, and 21 tons of quartz crushed yielded 770z. 13dwt. of gold. An average of three men were employed. Several other licensed holdings have been worked, but no great returns have been obtained. Owhaboa District. Smile of Fortune Mine, 12 acres 3 roods 2 perches (Mr. John Abbott, owner). —This mine was worked by Farmer and party, tributers. Six men were employed, and 341 tons of quartz crushed, yielded 3330z. 15dwt. of gold. The workings were a continuation of the surface block on which they were engaged last year, and extending the low-level drive 314 ft. Waitekauei District. Waitekauri Mine, 9 acres 2 roods 23 perches (Mr. Thomas Henry Eussell, owner; Mr. William Hollis, manager).—Twenty wages-men were employed, and 1,500 tons of poor quartz crushed for a return of 131oz. lldwt. of gold. About 1,500 ft. of old drives were cleaned up and repaired, and 200 ft. driven on the hanging-wall of the main reef, the foot-wall portion having been taken out in former days. The quartz obtained was too poor to pay, and further works are to be carried on in opening up blocks of the reef which are intact. The battery, which now consists of one stone-breaker, thirty stamps, six pans (Howell's amalgamating), and three settlers, is driven by a 38ft. overshot wheel, the fall of water being 36ft. The tailings from the stamps are raised by an elevator and run into a series of settling-tanks, which enables the slimes to settle and the water to be again used in crushing, thus preventing loss in float-gold. The slimes and sand are drawn from the tanks and conveyed in trucks to the amalgamating-pans. The owner, Mr. Eussell, is satisfied that by this mode of treatment a large percentage of gold is saved. The tramway from the mine to the mill is 83 chains long and in good working order. Jubilee Mine, 108 acres (Mr. E. K. Cooper, owner; Mr. H. Baker, manager.) —Twelve wagesmen have been employed. The chief workings in the mine have been in opening up an intermediate level 400 ft. above the Home level. A considerable amount of quartz has been obtained, and a parcel of 10 tons forwarded to England; value, about £150. A tramway 58 chains in length is being constructed to convey the quartz from the level to the battery, which was erected several years ago to crush surface-quartz. The battery, which consists of ten stamps, one settler, one agitator, and five berdans driven by steam, has lately been overhauled and will soon be again ready. A large paddock of quartz is ready for crushing as soon as the tramway is finished. Very little work has been done in the other holdings in this district. Komata District. New Find Mine, 27 acres (Mr. Thomas Henry Eussell, owner). —A discovery of gold was made in this mine about the month of June last year, and a considerable amount of prospecting work was done by Tilsley, Worth, and party, the first owners. A cross-cut 30ft. in length was put in and two reefs cut through, the first reef being about 7ft. and the second about 12ft. in thickness, the distance between the reefs being about 15ft. Excellent prospects of gold were obtained, and a ton of quartz crushed at the School of Mines, Thames, yielded twenty-one pounds' worth of bullion. Mr. T. H. Eussell, the present owner, entered into negotiations for the purchase of the mine, and took in hand the work of further opening up and testing the value of fche reefs. He then caused a drive of 70ft. to be put in on the second reef, and he says " good milling-ore was found throughout;" he also put in a cross-cut 30ft. below, and cut the second reef at a distance, in the tunnel, of 50ft. The first reef was here 10ft. and the second about 12ft. in thickness, the distance between them being only sft.; this shows a tendency of the two reefs to close in and perhaps become one underneath. Both the first and second reefs are worth 30 per cent, more per ton than they are above in the upper level. Mr. Eussell has had 100 tons of the quartz taken from the both levels, packed, and sledged to the Waitekauri Battery, a distance of about three miles, and treated there. The bullion obtained was worth £700. A substantial wooden tramway is now in course of construction from the mine to the Waitekauri Battery, and as soon as it is completed the battery will be started on the ore from this mine. An average of ten men were employed during the year.