stone-like coal

例句：

1. 1. The mine produces a type of stone-like coal that is used in heating systems.
   这个矿生产一种用于加热系统的似石煤。
2. 2. The company has been using this type of stone-like coal for years to power their factories.
   这家公司多年来一直使用这种似石煤来为他们的工厂提供动力。
3. 3. The stone-like coal is mined from deep within the earth's crust and is considered a valuable resource.
   这种似石煤是从地球地壳深处开采出来的，被认为是一种宝贵的资源。