One section of its walls of grey Delhi quartzite had collapsed.

一段灰色的德里石英墙已经倒塌。

Geochemists at Columbia University found a lode of quartzite, a metamorphic rock formed from sandstone, on the Indian Ocean island of Anjouan.

哥伦比亚大学的地球化学家在印度洋昂儒昂岛上现了一个石英矿脉，石英是由形成的变质。

This is because the stone balls were made of different types of stone including sandstone, green stone and quartzite.

这是因为石球是由不同类型的石头制成的， 包括、石和石英。

Before  chip manufacturing at the fab, we first have to manufacture the silicon  wafers by refining quartzite into pure silicon, and then growing a monocrystalline ingot  and cutting it into wafers.

在晶圆厂制造芯片之前，我们必须首先将石英提炼成纯硅，然后生长单晶锭并将切割成晶片， 从而制造出硅晶片。