In fact, there is a pillar there of high purity zinc that stood for the duration.

事实上，那有一个高纯度锌的柱子,存在于整个时期。

麻省理工公开课 - 固态化学导论课程节选

It is almost a thousand years now and it is in high purity.

到现在差不多一千年了,还是保持在高纯度。

麻省理工公开课 - 固态化学导论课程节选