Abstract: The X-ray pre-concentration test of Dajingzi copper-zinc ore by X-ray sorting machine was carried out. The results showed that when the threshold value was 0.09， the copper and zinc grades of the concentrate were obtained after the pre-selection process is 0.90% and 0.73%， the recovery rates of copper and zinc were 99.46% and 98.80%， respectively， and the tailing rate was 18.09%. Compared with the original ore， the copper and zinc grade in concentrate increased by 0.16 and 0.13 percentage points， respectively. The analysis on tailings properties indicate that the copper grade in tailings is 0.028%， the zinc grade is 0.036%， the copper and zinc grades are very low， SiO2 content is 63.13%， Al₂O₃ content is 14.48%， and TFe content is 7.32%， a small amount of CaO， MgO and K， which indicate that the main component of the tailings is gangue minerals. SEM and EDS tests on the pre-concentrate concentrate show that the pre-concentrate concentrate mainly consist of gangue minerals such as quartz and chlorite. Mainly， the mineral composition particle size is extremely uneven， and the intercalation relationship between minerals is more complicated. After pre-concentration the X-ray sorting machine for Dajingzi copper-zinc ore， the grade of the selected ore can be improved， the amount of waste rock selected can be reduced， and the comprehensive benefit of the plant can be improved.

Key words: X-ray Sorting Machine, Pre-concentration, Copper-zinc ore, Overall benefit