It occurs chiefly as stannic oxide , SnO 2 in cassiterite.主要以氧化物状态存在.One of the key problems in its origin is the solubility of cassiterite in granitic melt.锡石在花岗质熔体中的溶解度,是阐明花岗岩全岩型锡矿成因的关键....
劳驾你服从我要给出的指令好不好?Will you kindly obey the instructions I am about to give?劳驾,买单。Can we have the bill please?劳驾你帮我做这件事好 吗 ?Would you be kind enough to do it for me?...