CRUSHING BATTERY.

Hauraki Plains Gazette, Volume XXXIX, Issue 5293, 29 June 1928, Page 3

CRUSHING BATTERY.

THE RISING SUN CONSIDERATION BY COMMITTEE. A ’meeting of the district committee appointed to consider the proposals submitted by the Rising Sun Gold Mining Co., Ltd., relative to the> establishment of a public crushing battery for the trea.tnie.nt of orc was heldl at the .fiteniciipal Chambers on Wednesday mght. The Mayor of Paeroa (Mr W. Marshall) was appointed chairman and Mr F. E. Flatt secretary. The principal business, before the meeting was the consideration of the company’s proposals and the drawing of something concrete, for presentation' to the Government by .a deputation which, will later go to Wellington with a request for financial assist, ance. Much important work was done by the committee, and it was decided to hold the nxet meeting at Wa.ihi. Included in the information supplied by the company w.as an estnnaic ' that the present value of the Rising Sun battery at Owharoa. was approximately £7405. Under the present arrangement tlie battery was capable of treating about.eight tojis of ore a. shift of eight hours, or 24 tons a day of 21 ’ hours, the treatment being amalgama- ' tfon, concentration cyanide treatment of sands by percolation, and slime treatment by decentration and mechanical agitation- With that method of treatment an extraction of about 75 per cent, of the values, contained was 1 on free milling ores such az were found in the surface levels of the mine, but it was unsuitable and entirely out of date for ore-s conta ning sulphides. In order to complete the plant and bring it thoroughly upto.date. so as to guarantee an extraction of at least 85 per cent, of the bullion content from sulphide ores as found throughout the district at reasonable cost, additional plant would be necessity at an approximate cost of £6095. In pointing out the advantages offered by the company the general manager, Mr R. M. Aitken, in h' ! s report stated :— “By purchasing portion of this /Jrblant second-hand and altering portion pf existing plant a saving, of about £loo'o might be effected. Theadditional plant would, increase the capacity of the battery to at least 35 to 40 tons per 24-hoiW day, would dfc- . crease working costs per ton, and save at lea t 85 per cent, of the bullioA contents on sulpbfde ores and prob- •’ ably 90 per cent, or over on free-mill-ing ores. “The plant could be used for crushing in cyanide solutions, and. ores, when suitable, would be treated by the all sliming cyanide process, by which method most ores in the .district yield a splendid l extraction, and all bullion ' contents can be recovered in New Zealand without shipment of coneentrater. to Australia, for smelting. 1 “With such a pla.nt the Rising Sun would be prepared to treat and purchase all gold -"id silver ores delivered, at their mill and guarantee an ex Action of 85 per cent, of the ;ss lip assay va.lue. less a treatment ~ charge of 20s per ton. In fact, they are prepared to allow the use of their mill as a public crushing battery under the following conditions: “That the Government advance the necessary capital to instal the additional plant. The approximate cost of such plant as per schedule is £6OOO. “That the Rising Sun Sun Gold Mining .Ltd., will guarantee to bring plant up-to-date and install new” pla.nt as specified. “That in the event of winding, up or upon request of the Rising Sun Gold Mining Co., Ltd., the Government purchase the company’s interest "X-T/i* the plant for the sum of £5OOO, being two-thirds of its present value. . and shall pay for any additional plant installed ajid any or all amounts paid them through sinking fund. “That the company will supply all expert knowledge, labour, and organ, isation of the working of the pla.nt, and shall treat or purchase ores delivered at their mill. “That the company will also maintain the plant at its own. cost, except if destroyed by fire, earthquake, or act of God'. , • ' “In order to supply sinking fund, company agree to set asidfe a of 2s per ton on all ore put through' their mill, both their own and publ’c. “That as consideration for the Rising Sun, Company enter!ng.into and -^undertaking'this work and using their and organisation, the Government shall give to the company a grunt of £2OOO. and the balance of £4OOO shall be by way of loan and be repaid without interest as already provided by way of sinking fund.” ADVANTAGES TO COMPANY? The advantages of an up-to-date plant to the Rising Sun Company may be summarised as follows: “An extra extraction of 10 per cent, to 15 per cent, of the bullion Contents means 10s to 15s per ton on ore worth £5 per ton, which on regular crushing ; .would pay the treatment costs. “It enables, the company to m,’ne and treat ore at a profit, ore which otherwise would be left i,n the mine. ton ore could be mixed and "twated at a profit with an up-to-date ifiant. “It reduces treatment costs per ton, and no *lditional men would be required to obtain 50 per cent, to 60 per cent more output, excepting on repairs ami renewals. “Power costsi would show a considerable reduction per ton of orc treated. aS air agitation is quicker and cheaper than the slow and costly methods of mechanical agitation.” DISADVANTAGES TO COMPANY. The disadvantages are : “That tlie Rising Sun Company •must be prepared at all times to handle parcels of ore for outsiders, plant must be kept to its full effi"viancy in order to return the purchase extraction guaranteed. “That outside parcels of ore will differ from the Rising Sun ore, and ■treatment must be varied according •"Jn the mineral contents. This entails jtn maily cases expert examination and experimental work. “More assay work will be entailed,

and extra supervision on parcels; being treated for the public. “Where ores contain lead, antimony, tclluridc-s. and other minerals, extra special treatment will be required, and extraction of these minerals by concentra.tioii and shipment for smelting may be necessary. ADVANTAGES TO GOVERNMENTThe advantages to the Government are : “That they supply the district with an up-to-date public crushing; battery in a most central position to suit Waihi, Waikino, Wajtekauri, Karanga. Jiakc. and surrounding districts at an exceedingly low cost of £6OOO. “That they are entirely free from the expense of working and maintaining a plant of tills description which, if run solely under their control to treat separate parcels as required, might easily cost from £3 to £5 per ton for ore treated. “That they have the services of experts to experiment and supervise tlie treatment of the ores without any cost. “That- tlie money advanced; is not an expenditure of capital, but is in the nature of a loan repayable by a royalty on a tonnage, basis crushed, while at the present time there is; alm’ost sufficient ore in sight in the Rising Sun property to ensure the repayment of tihe loan. “That a public crushing battery in the district will supply a want that is urgently required. It will stimulate prospecting operations over tine, whole field, and will Induce individual tribJ uters and parties of working miners to extract blocks of stone left in worked mines and discover new lodes which undoubtedly exist. Tn fact, it would tend to relieve to a large extent tlie unemployment now existing tinthese districts.”