QUAUTZ-CRUSHING MACHINERY.

Tuapeka Times, Volume V, Issue 231, 4 July 1872, Page 8

QUAUTZ-C RUSHING MACHINERY.

(From the "Daily Times.") • A large quanity of crashing machinery is now beins* made at the foundry Of Messrs. Kincaid, M'^ueen, and Co",<>

Co., Dunedin. The chief is a tenhead quartz crushing battery, for the Gabriel's Gully Quartz Mining Co., Tuapeka. The battery consists of two cc st-iron stamper boxes, containing five heads each, each head \*eighing scwt., 3qrs. The stamper boxes are on the front and back delivery principle ; that is the stuff crushed is discharged both from the front and back. The stampers are lifted with cams, which are made on what is considered to be an unproved principle. They are of iron, and are steeled on the face to insure their Avearing longer. - The discs on the stamp rods are of wrought iron, faced Avith steel, and can be screwed up and down to regulate the fall of the stampers. The machine is fitted with a hopper sufficiently large hold 40 tons of quartz. The bottom of the hopper being placed on an incline causes a quantity of stuff to escape from it into the feed shoots. The latter, of Avhich there is one to every five heads, rest on a fixed stand at one end, and on a strong spring on the other. When the stuff under the stampers geta too low, the spring supportiug the delivering end of the feed shoot is shaken, causing some of the quartz in the 1 shoots to be discharged into the stamper box, to which we have already referred. The ripple table is 13 feet long by 5 feet wide, and has -10 superficial feet of quicksilvered copper- plate, six quicksilver ripples, and two quicksilver wells. A practical gentleman lately arrived from the Thames, considers this table an improvement upon those in use there: The ordinary ripple has three ripples, some four or five feet apart, Avhile this, it may be observed, has six. At the end of the ripple table on which the tailings are received, there is a slope af about a foot, and on this slope there are three ripples at regular intervals from each other. They are each about two inches deep, and contain quicksilver. The pulverised quartz entering with the Avater into the first ripple, mixes with the quicksilver in it. The tailings escape from the ripple through a row of small holes, half an inch-in diameter in the ripj.le Inurd, pass through the second ripple, then through the fiird, on to the more gradual incline of the remaining twelve feet of the ripple table. There are three ripples in this part of the table, about two feet apart from each other, as in the ordinary table — but it is in. these through which the tailings' first .pass that most of the gold is saved. At the end, at which the tailings run off the table, there are two cavities called quicksilver wells, which are meant to catch my quicksilver that may be AA r ashed out of the ripples. The ripple table has between the ripples a copper surface, coal< j d with quicksilver. It may be mentioned that at the Cromwell Company's claim, an ordinary table, and pne of the type here described, Avere in operation at the saaie time some time ago ; but as this table Avas found to be superior to the ordinary one in go Id-saviii2f qualities, the ordinary one had to give place tpone of the new description. The blanket table on which the tailings are discharged from the ripple, table.' is six feet Avide, and sixteen feet loner, and has four compartments. Instead of a shaking table, as is used in some machines, a concentrator is used in this. The concentrator is circular, about two feet- in diameter aud eighteen inches deep. The tailings enter at the level of the bottom of the concentrator on one side.. A number of rakes revolving in it round an upright spindle, churn the coutents ; the light tailings, being thrown upward, escape through an opening some inches above the bottom, while the quicksilver and gold being too heavy to escape, are retained. Che amalgam barrel, which is generally of wood irf made of iron to last longer. All the timber to be used on the foundation is to be black pine from the Tapauuibush.

The machinery is to be driven by a reaction turMne wheel three feet in diameter, which is to have two jets. The wheel is to work up to 30 horsepower, and is to be supplied with" water conveyed in pipes down a slope hav'ng a fall of 100 feet perpendicular. The piping conducting the water to the wheel is to be of wrought iron, find guaranteed to bear a pressure of SOlbs to the square inch.

Tasmania is about to put in a claim; For being a diamond-bearing country. ■A Launcestou journal says: — "The •him. 1). Erskino, Colonial Secretary of the Colony of Natal, who,, at one time ■luring his career as a military officer, was stationed in Tasmania, has sent to tbe Colouial Secretary here a box containing a quantity of the earth in which the Cape diamonds are found, for the_ purpose of enabling local zoologists to state whether any similar f brma!jon exists in this Colouy. This ■"firth having been submitted by Mr. Wilson to a gentleman of extensive i n i i io ra logical knowledge, he has re.lortod that, although he cannot point hi any precisely similar deposit in Tasmania, he is quite satisfied that were such seai;ch made, diamonds would be found here as well as in the idjaront Colonies. He also mentions the district of Hythe, at South port, as presenting strong geological indications >f the existence of these and other precious stones."

The " Ross Guardian " (West Coast) says ; — There never was a cloud but that had a sil.ver lining, and turning from Jones' Flat, on which the prospects are go black •# present, we are

happy to state that some very good specimens of quartz, in which gold is plainly visible, were shown yesterday by Mr. Duncan Macfarlane, the manager of the Donnelly's Creek Quartz Reef Company. The stone was obtained about eight feet from the surface. The vein at this depth is about three inches thick: but a tunnel is being driven into the hill to strike it at about 150 feet, at which depth a good body of stone is expected to be met with One of the specimens is pure quartz ; the other a kind of slate casing. This company has been very persevering, and on their sviccess depends the opening or quartz reefs in the Totara District.

The crushing i-eturris from the Thames for the last month show that 7787 tons of stone yielded 16,050 ozs. of gold.

In Victoria they can now crush quartz at a profit that will only yield 2dwt, and can so treat their tailings as not to lose a penny- weight per ton of pyrifcous gold.

The "Maryborough " Advertiser ' (Victoria) of a late date says : — An impoitant discovery of gold has been made at Carisbrook, an^ has just leaked out. A parby of Chinamen who were working a claim at Porz's (generally termed Potts') paddock, near Harrison's Hill, last' week came on a monster nugget weighing 331 b. The matter was kept dark by the wary Celestials until the last day or two, when the fact became known,, and produced quite a sensation. From the position of the ground it is believed that the spot on which the treasure was found will prove to be a new lead. - The latest accounts of the South African diamond fields are not so favorable. The " Cape Argus," in its issue of March sth, says :— " The finds of diamonds are sensibly decreasing, and it is considered that the discovery of any more rich fields is improbable. The reported discovery of a diamond weighing 1100 carats is now found to be a hoax. Accidents are frequent at the Fields, and in several instances lives have been lost." The s.une jonrnal says that " the reports of the gold discoveries at Marabastadt are said to be much exaggerated. Another new rush, called- James' Kopje, has turned oufc a complete failure."