Microscopically the ores are medium grained to amorphous.显微镜下,矿石为中粒至非晶质.The only local coarse - grained sand - stones in the uppermost part are important for uranium.仅最上面局部的粗粒砂岩对铀是有利的.Fine - grained clay may settle out i...

migraines的音标：...