nemathecium

例句：

1. 1.The nemathecium is a rare and valuable mineral found in the earth's crust.
   地幔矿物是一种稀有且珍贵的矿物，存在于地球的地壳中。
2. 2.The nemathecium has been used for centuries to treat various ailments.
   地幔矿物被使用了几个世纪来治疗各种疾病。
3. 3.The nemathecium is a key component in the production of many industrial products.
   地幔矿物是生产许多工业产品的关键成分。