Show GETTING ALL VALUES IN PLACER GRAVEL WASHING accomplished BY NEW SCHEME A new scheme of combination sluicing is said to be yielding I 1 fine results in some of the california pla cering districts according to the siskiyou you news C V averill manager of the northern branch of the state mining bureau the paper quoted states gave a talk before the redding chamber of commerce recently on the subject of gravel mining he said that this kind of mining was increasing in popularity among those seeking for the hidden gold of the streams mining is largely hydraulic in trinity sis ciyou and sierra counties while in nevada plumas and in the seneca district drift mining is the favorite method averill stated that the usual methods of trying to save gold in riffles fiffles are crude even when special devices were used to save the fine gold because a stream of water strong enough to wash away the coarse gravel will also wash away fine gold proof of this may be seen in old gravel deposits which have been worked over three and four times at a profit notably in plumas county in this age of refined machinery when it has been developed to perform with a high degree of efficiency all kinds of difficult tasks it is not surprising to find that efforts are being made to develop something which will save all of the gold from the gravel with one handling A machine now in operation at seneca and observed by averill apparently accomplishes this the machine is set below belov the conventional sluice and rif fles the gravel flows from the sluice to a shaking hopper which contains a double screen coarse material is rejected over the tops of the screens the fines pass through to a vibrating table made of corrugated metal which in the particular machine observed was said to be saving 10 pounds of concentrate p per er ton of gravel this concentrate being worth 1 per pound |