eluvial placer

例句：

1. 1.The eluvial placer is a rare mineral that can be found only in specific areas.
   矿砂是一种稀有矿物，只能在特定地区找到。
2. 2. The mining company has been searching for eluvial placers for decades.
   这家矿业公司已经寻找矿砂层几十年了。
3. 3. The eluvial placer was discovered by a team of geologists during their research trip.
   地质学家团队在一次研究旅行中发现了矿砂层。