JIANG Quan, YANG Yong*, TANG Yun, PIAO Hai-shan

(1. School of Mines, Guizhou University, Guiyang 550025, China;
2. National and Local Joint Key Laboratory of Efficient Utilization of Advantageous Mineral Resources in Karst Areas, Guiyang 550025, China;
3. Guizhou Provincial Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources, Guiyang 550025, China)

Abstract: By studying the process mineralogy of two kinds of ores, the high graded phosphorous strip and the dolomitic strip, in the Zhijin rare earth phosphate deposit in Guizhou Province, the mineral components, occurrence state characteristics of rare earth elements and trace elements of the ores have been explored. The distribution, enrichment rule and mutual relationship of different chemical compositions at different grain sizes have been studied emphatically. Considering the reduction of Si, Mg and Fe in ores, this study provides the basis for the crushing process of raw ore and the choice of beneficiation scheme. The results show that the phosphorous strips belong to high graded calcium-magnesia phosphorite with an average P2O5 grade of 35%, average MgO content of 1.37% and average SiO2 content of 5.76%. Apatite is the main useful mineral with its percentage of 74.95%. Apatite is closely embedded and intergrown with dolomite, quartz, calcite, pyrite in ores. The dolomitic strips have the average P2O5 grade of 8.35%, the relatively high average MgO content of 14.58%, and the average SiO2 content of 8.12%. The dolomitic strip belongs to low graded calcium-magnesia phosphorite, with percentage of 22.99% for apatite which is the main useful mineral. The main gangue minerals of this kind of interbedded phosphorites include dolomite, quartz, pyrite and so on.

Keywords: phosphorous deposit; occurrence location; embedded grain size; phosphorus strip; dolomite strip

ACTA MINERALOGICA SINICA Vol. 43, No. 3, 2023, Page 358