Minings News.

Te Aroha News, Volume VII, Issue 477, 4 June 1890, Page 2

Minings News.

MAROTOTO.

Marototo Gold and Silver Mining Co. t It is now soil)© three years ago since Mcßrinn, the discovered the reef upon which the Mnrototo G. and 8. Mining Co. have ever since operated with considerable success, but it wns nnttill about six months ago that the directors decided to erect ’a small reduction plant upon tho mine,for the purpose of treating the ore on the ground. A site was selected in a gifilv about a quarter of a mile distant from the rnino, down through which what is known as Mcßrinn’s Creek flows, the water from which is being utilised to provide the necessary power for working the pi- a’. Upon this siteamoßt substantial weatherboard building, built from the best heart of kauri timber cut and sawn on the spot, has been erected, its dimensions being ,20 feet by 30 feet. A dam Tins been built across the stream soma few chains higher up the gully, near the mouth of the low level driven by the Hikutaia Gold Mining Company, and a race constructed for a length of chains, which provides a fall for the water of 110 feet, the race being connected with the building by IU-inoli iron pipes. The plant itself comprises two of McKav pans and a settler, which are driven bv one of Messrs Price Brothers’high-pressure PeTton wheels. 3 feet 6 inches in diameter. Tho erection of the plant was completed just about a month ago, since which time about 35 tons of second-class ore has been treated, together with about 7cwt of ore of a superior grade, and the amalgam obtained therefrom when retorted, yielded 1600oza. lOGwt. of melted bullion, worth about 68 07..,0 7.., which is considered to he a very sutisfa'tor,- return. The process of treating the ore, is somewhat ns follows i A charge of about 6cwt. of ore, together with a quantity of water, is first placed in each pan, which is then set in motion. After grinding this charge about two hours and a-lr If, by whL-h time it is reduced to a thick pnste, 401bs to 501hs of quicksilver are then thrown into the mixfere, together with about 4lb« of salt, and then the pans are again set in motion, and kept grinding for another hour and a-half. At the end ot this time the amalgamation has taken place, and the whole contents of the pans are rim off into a large settler, which is provided with four revolving arms going round about twenty revolutions per minute. Tin’s so agitates the liquid that nil the silver fills to the bot- : tom, where it in drawn off by a syphon, the refuse being gradually taken away from the pan by a series of plug holes placed nt various heights. This completes the tnoduit operands, the silver on being taken off being ready for squeezing and retorting. Operations in the mine are at present only of a limited nature, as the passes are full of ore broken ready for treatment, and the manager is desirous of reducing the tonnage on hand before taking any further steps to materially increase the supply. It is estimated there are from four to five tons of first-class ore on hand worth about L2OO per ton, 70 tons of seeond-cJass ore worth about L 25 per ton, and a large quantity of third-class ore worth about L 5 per ton. The mine is well opened up, the reef having been developed and tested for a length of over 800 feet, and three distinct shootß of payable ore proved to exist in it. The workings are connected with the plant by a good sledge 'track, about a qunrter of a mile in length, so that no difficulty is experienced in getting the ore down to the plant. Great credit is due to Mr Moore for the thoroughly systematic manner in which he has opened up the mine, and also the highly satisfactory way in which the erection of the plant has been carried out, especially when the great difficulties he had to contend with in getting the '’machinery, on the ground, owing to the precipitous and mountninous nature of the country, are taken into consideration. He has certainly conserved the interests of the shareholders to the utmost extent, and well deserves the success which his efforts are now likely to result iri.