horsetail ore

例句：

1. 1. The horsetail ore is a valuable resource for the local economy.
   马尾矿是当地经济的重要资源。
2. 2. The mining company has been extracting horsetail ore for decades.
   这家矿业公司几十年来一直在开采马尾矿。
3. 3. The horsetail ore was used in ancient times as a source of gold and silver.
   马尾矿在古代被用作黄金和白银的来源。