| Show MILLING THE overburden press bulletin bingham utah something in connection with utah copper which is not generally known or at least is not fully appreciated is that during the last several months a large proportion of the material put through the big mill at garfield has been the overburden over burden or covering of the porphyry ore deposits material which was not originally counted upon as carrying mineral in commercial quantities this overburden over burden carries one per cent copper and less it is stripped from the porphyry ore with steam shovels so far as reports upon the property show its utilization has never been contemplated but in the course of practical mining operations it became a matter of economy to send quantities of it to the mill with the ore rather than to employ the additional labor required to segregate it and instead of bringing tar ane average values down below the pay mark as might have been expected the mill continued to grind out profits at almost the regular rates the latest quarterly report of the company showed that the handling at the mill of an unusually large proportion of the low grade stock combined with transportation difficulties had served to raise the cost of producing a pound of copper the fractional part of one cent a pound but it is a question if in the long run it will not in reality prove a profitable proceeding it has at least confirmed the managements belief that it is on the right track in evolving a special process for treating the rock once regarded as purely waste material plans are out for a new section of 0 the big mill in which the new process will be tried out and judging from the success already attained in an experimental way there is almost no doubt that a large additional saving lavint will be effected but the demonstration already made by utah copper that of making earnings in excess of its regular dividend requirements when experimenting with rock regarded as too low grade to be commercialized which its mill was not devised to handle and doing that at a time when the metal is at bedrock prices is assuredly a notable accomplishment ment in modern mining and metallurgy |
