refractory ore

例句：

1. 1.The mining company is looking for a new source of refractory ore to replace the old one.
   这家矿业公司正在寻找新的难熔矿石来替代旧的矿石。
2. 2.The refractory ore was extracted from deep within the earth's crust.
   这种难熔矿石是从地球地壳深处提取出来的。
3. 3. The refractory ore has been used in various industrial processes for decades.
   这种难熔矿石已经被用于各种工业过程几十年了。