【摘要】 <正> 贝塔石(Betafite)是一种含铀的铌钛酸盐矿物,我国研究得尚少。本文从地质产状、物理性质、光学性质、矿物化学、X射线特征和差热分析结果诸方面作一简要的报导。一、地质产状所研究的贝塔石样品取自某地槽区背斜轴部的太古代变质岩和燕山期花岗斑岩体的各类岩脉中;这些岩脉包括花岗伟晶岩、霓石正长岩、石英斑岩和石英碳酸岩脉,其中以花岗伟晶岩脉和石英碳酸岩脉含贝塔石最多。更多还原

【Abstract】 Betafite, a U-bearing niobium titanate mineral, is black in colour in granite-pegmatite veins, and yellow brown or brown in quartz-carbonate veins.Chemically, black betafite is high in CaO and UO₂ and low in Fe₂O₃,UO₃, H₂O⁺ and H₂O^- while yellow brown betafite shows an opposite situation, indicating that the former was formed under relatively reducing conditions and the latter under considerably oxidizing conditions.The REE distribution pattern in betafite is noted for ∑Ce>∑Y. The DTA curve of black betafite is different from that of yellow brown one. Due to the higher content of UO₂ in black betafite the phase transformation of UO₂ to UO₃ begins at 510℃.The formation of betafite is closely related to alkali-metasomatism.更多还原