chemical fossil

• 化学化石,化学的化石

chemical fossil的用法和样例：

例句

1. No wonder I mistook it as a tree fossil.
   怪不得我以为它是古树的化石呢。
2. A shiny fossil "stone" called amber is in a beautiful box.
   一种名为琥珀的光彩夺目的化石在一个漂亮的盒子里。