THE EXTRACTION OF FINE GOLD FROM TAILINGS.

Mount Ida Chronicle, Volume I, Issue 30, 27 August 1869, Page 3

THE EXTRACTION OF FINE GOLD FROM TAILINGS.

(From the Pleasant Creek News.) Of late months Pleasant Creek has gradually awbke, to the fact that the thousands of tailings which are lvinoabout in all directions are valuable"; that considering the crushed quartz to be upon the surface> arid ready for opewithout the labor-and expense; of raising, we; have amongst us a great' source of wealth, which can at anytime I be made to yield most profitable re- ! turns. This knowledge, or rather its practical effect of making claimholders refuse to sell tailings at anything but an exorbitant price, has been' broiio-ht about through- the experiments of one man, who has, to his own satisfaction, and to the surprise" of others, worked out a problem for catching-these most minute particles of fine gold which invariably escape by the use of flowing water. The numerous efforts - which have been made to make the further treatment of tailings payable, have been wholly based upon the principle of disintegration. By the process we refer to such particles of gold as may be held by the particles of crushed quartz are'not sought for, but simply the fine gold which remains amongst the tailings .and which may be described as unfettered by combination with'the stone. Thelnventipn for the ■saving of gold such as this is perhaps one of the simplest that has dawned upon claim managers for years. It is ' far- more effective because the returns .are twice or three times as great as those attained by the buddle, while any amount of tailings may be treated. The discoverer of the invention, "Robert Tweedie, of Pleasant Creek,' has his rough machine at work, by which he is at present busily employed in treating mullock ; that is to say stuff which, by the common test of the tin dish, will not reveal the color. We will first IDroceed to describe the process, which will require but a very short explanation, after which we will give the result ! of Tvveedie's trials of the tailings of | the different machines. The whole of the machinery requisite is a large iron basin, the plates composing which resemble the segments of an orange • they are fastened with the one overlap pinothe other, so that we presume the junction of the plates forms ripples, which doubtless assist in the amalgamation. This basin is fixed for revolving at an augle of about 25 degrees, and here lies one of the principles'which the process embodies. When we say that the rate of the revolution is also slow, and that the tailings are treated with quicksilver, and with barely sufficient water to form a pulp, we relate the whole of the process by which an average of five pennyweights to the ton is extracted from the : ; Pleasant Creek quartz tailings—by which mullock or refuse which has been treated by Europeans and Chinese is again taxed by Tweedie, arid yields liim a return of three to four pennyweights to the ton. The plan will be readily conceived when we explain that the slow rotatory motion of the plan disturbs the tailings pulp just sufficiently to carry it to almost the top of the pan in its revolutions, from whence it falls down to the bottom, rolling and rolling over by the slow continuous motion, so that every particleof the tailings is exposed, and turned, and moved; and exposed again so regularly and constantly that it becomes simply a matter of impossibility that any particle of the pulp can escape permeation by the quicksilver, or that any particle of gold, no matter how fine, can escape being gripped by it. The proof 6f ihe emcaey of a process of this nature is simply to be found in the result. The basin now used by Tweedie is small as compared with those which he has ordered at Ballarat, but he is able to treat now almost two tons in the twentyfour hours; with alargebasinhe will be able to treat four tons per basin. Tweedie assists the 'amalgamating process much by the use of alum and carbonate of soda. This has the effectof causing the flowing globules of mercury to unite, or those particles which, in amalgamating parlance, are called "sick." It will scarcely be credited how fine is the yield which is thus saved. The operator will take a shovelful of the pulp, and after washing it off in the usual manner, the inquirer is just able, by very close scrutiny, to discern a yellow tinge upon the edge of the washed sand. This is the quality of the ' gold saved from the tailings by the process we have

described. In the new basin there are three taps, one below the other; the first to let off the refuse, the second for pyrites, aDd the last for the sediment in which the amalgam is contained. Tweedie states that one man can with ease attend to twenty ba inn, and he reckons at. a moderate calculation from one basin, four tons per twenty-four hours. Tweedie has taken out a patent for his process. The: cost of a basin with requisite gearing for horsepower is £25, the royalty in each of which is £lO, and £2 per month. The results obtained by Tweedie are little short of startling to those who know the vast accumulation of tailings in the Colony. At Pleasant Greek, for example, where the amalgamating process, and where the appliances for saving the gold are of the best, the operator has found that he can obtain the folio wing yields from, the different machine tailings :—Eose of Denmark, 5 dwts. to the ton; Cambrian, s|dwt. to the ton; Moonlight, 9dwt from half a load (supposed to be not an average); .Lamont's, 9dwt. irom half a load; Davidson's, 3dwt. 19 gr.; Jeffrey's, 3dwt. to half a load; jNfewington, 3dwt. to the ton; Leviathan, 4dwts. and some grains to half a load. We must almost refuse to believe that the above returns are fair averages of the refuses which has yielded up all that the stampers can take out, but when we learn that the price offered by Tweedie allows him but a liberal margin on these yields, and that claimrefuse to sell, we may fairly conclude that the "quartz tailing" era is beginning. Thus we hear that the inventor ha 3 offered as much as £l6 per ton for blanket tailings, and has not been able to obtain them at that price. _He has offered a price for common tailings, of which there are scores of thousands of tons here, at a rate which considering the distance to his machine, would require to yield an average of from 4dwt to sdwt per ton to pay him, but he cannot buy them. One gentleman who assisted Tweedie all through his efforts at perfecting his invention would have been very glad to dispose of the tailings of the machine of which he is manager at a low price, but when he saw the result of the process, he was compelled to decline the sale of the tailings, in justice to those for whom he acted, and in view of the company's power of obtaining the patent, and working the tailings on their own behalf.