Thwaites 's home-made toaster is a simpler affair , using just iron , copper , plastic , nickel and mica , a ceramic .

思伟茨的自制烤面包机要简易些，只用了铁、铜、塑料、镍和云母（一种陶瓷材料）。

So too the geologist does well to regard granite as a compound of quartz , felspar , and mica .

又如地质学家认花岗石是由石英、肉色石、金星石合成的，也是很对的。