Why Is Glass Transparent?

Today, glass is hard to imagine from our everyday life: whether as a window pane, drinking vessel, bottle or mirror – everywhere we encounter the hard, smooth and translucent material. But why is the glass transparent, although its starting materials, quartz sand with admixtures of soda and lime, seem rather opaque-white? "Glass is transparent for two reasons: On the one hand, there are no grain or material boundaries in the glass that would sca…