“云母”造句
属于这类物质的有
云母 、 瓷器 、 石英 、 玻璃 、 木材等等.
To this class of substance belong mica, porcelain, quartz, glass, wood, etc.
沥清铀矿和铜铀
云母比纯铀的放射性强得多.
Pitchblende and chalcolite are much more radioactive than uranium itself.
它不能通过
云母这样的不透水的物质.
It could not pass through material impervious to water such as mica.