WEI Jun-qi1,2*, ZHU Dan1,2*, WANG Fang1,2, LI Jian1, LU Li1,2, PAN Shi-yang1,2
(1. Hubei Geological Research Laboratory, Wuhan 430034, China;
2. Key Laboratory of Rare Mineral Experimental Technology, Ministry of Natural Resources, Wuhan 430034, China)
Abstract: Through whole-rock chemical analysis, microscope identification, scanning electron microscopy analysis, and automatic mineral quantitative analysis (AMICS), the chemical and mineralogical compositions and occurrence state of niobium and tantalum of ores in the Duanfengshan Nb-Ta deposit have been ascertained. The ores contain Nb2O5 contents varying from 0.0112% to 0.0117%, and Ta2O5 contents varying from 0.0033% to 0.0084%.They are mainly composed of minerals including albite, quartz, muscovite, biotite, and kaolinite. They contain main types of niobium-tantalum minerals including manganotanlite (Ta/Nb=2.94,Fe/Mn=0.45), manganotapiolite (Ta/Nb=0.51, Fe/Mn=0.56), and mangancolumbite (Ta/Nb=0.11, Fe/Mn=0.82). The deposit belongs to the granitic pegmatite-type niobium-tantalum deposit. The distribution rates of niobium in manganotanlite, manganotapiolite, and mangancolumbite are 48.76%, 37.26%, and 13.99%, respectively. The distribution rates of tantalum in manganotanlite, manganotapiolite, and mangancolumbite are 62.65%, 28.96%, and 8.39%, respectively. The particle sizes of niobium and tantalum minerals vary mainly from 16 μm to 75 μm. The degree of monomer dissociation of minerals is low, with the ratio of 24.47%.
Keywords: Niobium ore deposit; AMICS; mineralogical characteristics; occurrence state; Duanfengshan
ACTA MINERALOGICA SINICA Vol. 41, No.3, 2021, page 319-326