Abstract: Vein quartz is a kind of high quality silicon resource as an ideal raw material for processing high purity quartz. The process mineralogy of vein quartz was studied. The differences of samples with different size fractions after crushing or grinding were also analyzed. The experiments of iron removal by magnetic separation and feldspar and mica removal by flotation were carried out on four samples of -0.6+0.1 mm grade, -0.1+0.045 mm grade of raw material and -0.6+0.1 mm grade, -0.1+0.045 mm grade of grinding product, respectively. The results show that the vein quartz mainly consists of large quartz grains and the gangue is mainly muscovite, feldspar and a small amount of iron minerals. The content of SiO₂ in -0.6+0.1 mm grade, -0.1+0.045 mm grade of raw material and -0.6+0.1 mm grade, -0.1+0.045 mm grade of grinding product are increased from 99.10% to 99.62%, 99.74%, 99.67% and 99.66%, respectively. And the contents of Fe₂O₃ in each sample are decreased from 609.55 μg/g to 70.26 μg/g, 69.90 μg/g, 38.64 μg/g and 40.33 μg/g respectively. In general, the purification effect of -0.6+0.1 mm grade of the grinding product is the best, showing that the classification separation process is beneficial to the purification of vein quartz.

Key words: vein quartz, process mineralogy, classification, purification, magnetic separation, floatation