TEM and XRD results showed that opals in the palygorskite opal layers of palygorskite clay deposits at the boundary between Anhui and Jiangsu Provinces are divided into opal-A and opal-CT.

• TEM和XRD研究表明,在苏皖坡缕石粘土矿床的蛋白石坡缕石层中存在opal A和opal CT两种结构的蛋白石。