Archaeologists found that these ancient walls were built with bluestones transported from Wales.

bluestones 是复合名词，由 blue（蓝色）和 stones（石头）组成，字面意思是"蓝色的石头"。在考古学中特指一种带有蓝色调的砂岩或玄武岩，常用于古代建筑。