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another 750 ft. before it will cut the lode. When this level is completed it will give 55ft. of backs to the smithy level. After the lode is taken out to this depth further workings will have to bo carried on from a shaft, as this is the lowest level that can be constructed to bring out the ore on a natural gradient to the calcining-kilns. During the year ending the 31st March last 11,319 tons of quartz have been crushed, yielding 18,4080z. of bullion, which is said to have an average value of £1 4s. lid. per ounce. This would represent a value of about £23,002. But according to the returns published in the Thames Advertiser in April last, the value of bullion produced from July, 1889, to April 8, 1892, was £55,513, and, taking the figures from April, 1891, to Bth April, 1892, the value of the bullion produced for this period, was £28,525, which is £5,523 more than the estimated amount already shown for last year. The return is now, however, increasing largely, the value of the bullion obtained in May last being £5,000 ; also, during the same period an average of ninety men have been employed in the mines, and sixty men in connection with the crushing-battery and surface. Since my last visit an additional crushing-battery of thirty heads of stamps (American pattern) has been erected and used as a wet-crushing battery, while the thirty heads formerly erected are still used for dry crushing. Before giving the comparative results of dry and wet crushing, a description of the new additional plant may not be out of place, as the process of treatment of the pulverised ore, and methods used, are entirely different from those adopted at any other crushingplant, with the exception of the one recently erected by Mr. Eussell at Waitekauri, which is a facsimile of the plant in question. The stamps are 9001b. each, making ninety-two blows per minute, with a drop of six inches. The gratings are made of brass-wire gauze, 60 mesh, or 3,600 holes to the square inch. The water and pulverised pulp falls into a narrow chute, which runs along the whole width of the battery, close up against the stamp-mortars. This chute conveys all the water and pulp outside the building, where an elevating iron wheel is erected having buckets on the inside of the rim. The chute delivers the sand and water into the buckets, and the wheel, which is 26ft. in diameter, and about from 12in. to loin, in width, in breast conveys the material up to a height of about 24ft., the wheel making two and a half revolutions per minute. This elevating wheel is far preferable to the common elevators, and the wear and tear is almost nil. This elevating wheel delivers the water and pulp into a chute, which conveys it away to a series of settling-tanks. The settling-tanks are erected on heavy framing, so that a truck can pass underneath the trap-doors, from which the sand and sludge is discharged when the tanks are full. There are seven large tanks, each 16ft. by 14ft. and 14ft. deep, placed alongside each other; three of these tanks are used for settling the coarse sands, and four for the settlement of the sludge and slimes. The tanks for the coarse sands have an inverted A bottom, having two cast-iron doors on each side of each tank, from which the sand is discharged into a truck; but during the time the water and pulp is filling the tank, the cast-iron door is held fast against an indiarubber joint with set-screws. The four tanks for the settlement of the fine sludge and slimes have a V-shaped bottom, with valves which can be opened to allow the slimes to fall into trucks ; these trucks, when full, are run on to a cage and hoisted up to the level of the floor where the combination-pans are placed, by a hydraulic lift. The water after leaving the last tank is tolerably clear, and flows away in a chute, and is used again with a little additional water in the battery, so that as far as possible any loss of gold in the water is prevented. The process for extracting the gold is exactly similar to that described in my last report— namely, amalgamation in combination-pans and settlers, only ; no sulphate of copper is now used, but to every charge of 1,6001b. of wet ore 81b. of salt is added, and 1501b. of mercury; steam is used in each pah, and the temperature kept up to about 180°. About four hours is necessary for each charge. The charge of dry ore in each pan is 1,8001b., being 2001b. more than that of the wet ore. The fine slimes from the wet-crushed pulp are of too thin a consistency to amalgamate in the pans ; these slimes have to be mixed with either dry pulverised ore, or the coarser material from the wet-crushed pulp, before a satisfactory result in the extraction of the bullion is obtained. In regard to the comparative results of treating the dry-crushed ore and the wet pulp, the percentage of bullion obtained is in favour of the dry-crushed ore. In treating the dry-pulverised ore from the Union mine about 85 per cent, of the gold is obtained, and from the wet pulp about 75 per cent. The Martha does not give quite so high a percentage, about 70 per cent, and 60 per cent, respectively,)but the silver saved from the dry ore is said to be 40 per cent, of the assay-value, whereas from the wet pulp only about 25 per cent, is extracted. When the wet crushing-battery was first started the ore was crushed in its raw state as it came from the mine, the grating used being 60-mesh, the same as that used for dry-crushing ; but it was found that this mesh of iron- or steel-grating got clogged up very quickly, and consequently would not discharge the pulp. Brass-wire gauze gratings were then used and found to answer very well, but it was found that no larger quantity of ore could be crushed by the wet battery than by the dry one, while the ore was not pulverised so fine. This led to an experiment being made with calcined ore, which increased the crushing capacity of the wet battery about 30 per cent. The whole of the ore is now calcined previous to crushing, and the result is that about 30 per cent, more ore is crushed by the wet battery than by the dry one, while the bullion extracted from the dry ore is fully 10 per cent, more than is obtained from the wet pulp. The whole of the shafting for driving the crushing-battery, pans, and settlers, is connected and driven by six Pelton water-wheels, each 6ft. in diameter, three of which are supplied with water from the Ohinemuri River, and three from another creek and reservoir. The rock-breaker—one of Wheeler's —the movable jaw of which has an eccentric motion, and produces a squeezing and grinding action at the same time, is driven by a 3ft. Pelton wheel, the steam-engine only being used for driving the battery when water is scarce. This company are now constructing a plant to treat their pulverised ore by a cyanogen solution similar to the Cassell process in some respects, but by an entirely different method of application. The process is known as " Bohm's patent." Mr. Bohm was at Waihi constructing his plant at the time of my visit. Instead of the pulverised ore being placed in large vats or agitators, as is done
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