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The formation of an enriched intermediate product or lean concentrate from ores of nonferrous metals by separation of coarse classes without crushing, grinding, or beueficiation greatly reduces the capital and running costs and reduces the delay in the exploitation of new deposits.If there is a uniform distribution of the components by fragment size, use is made of electronic methods of separating ores; oscillator separation makes use of simple apparatus and does not require reagents [1, 2].An estimate of the effectiveness of the oscillator method of separation has been made for disseminated lead and lead-zinc ores. The ore-bearing strata of the deposit are composed of recrystallized and sheared carbonates and sometimes clay rocks. ,Mineralization in the form of sulfide streaks is confined to the quartzitic and sericitic parts.Our research program envisaged testing ores for separability and predicting the technology of processing the intermediate separation products.The ore was separated on a mock-up of an oscillator separator in the form of a disk feeder in which, at the ore exit point, were successively fixed an inductive oscillator transducer [3] with worMng frequencies of 13 and 56 MHz, and a gate-type separator controlled by the signals from the transducer with the aid of an electronic threshold circuit. The throughput of the separator was about 10 toas/h for material with a fragment size of 150-50 mm.To study the separability we selected and classified a sample of about 8 tons of lead ore. For separation we picked out about 2 tons of ore of the 150-50-mm class with a lead content of 8.17%.Separation yielded intermediate products containing 20 and 10% of lead, with 27% extraction from the original ore. Iron was concentrated preferentially in the tailings from the separator.The limiting lead content at the separator was found by visual inspection of the ore samples. To find the closeness of the correlation between the lead content of a fragment and the level of the signal from the transducer, and to choose the type of signal (amplitude or frequency) and the optimum frequency for the transducer, we investigated the recovery of ore specimens from 50 fragments of the 150-50-mm class.Signals from the inductive oscillator transducer from each specimen were measured at 5.28, 13.56, and 27.12 MHz. It was found that the moisture contents of the specimens had practically no influence on the signal. The greatest dynamic range (from 0.01 to 11.5 V) was observed for the amplitude signals (increment, change of voltage in oscillator circuit) at 13.56 MHz. There was a close correlation between the signal amplitude and the lead concentration in the specimens; the nonlinear correlation coefficient was 0.821 and the equation of nonlinear regression, according to calculations by the method of least squares, was a=--10.26 (lg U+0.6) +29.33 arctg (Ig U+0.61 ~15.22. where a is the lead content in per cent and U is the amplitude of the signal from the transducer in volts.From the analytical relations it was found that the minimu...

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