fine gravel

1. 细砾：fine dust 粉尘 | fine gravel 细砾 | fine sand 细沙

2. 細石礫：fine-grained environment 細粒環境 | fine gravel 細石礫 | fine sand 細砂

3. 細碎石：Filter-feeding 濾食性 | Fine gravel 細碎石 | Fine sand 細砂

4. 细砾,细砾石：fine graphite ==> 细石墨 | fine gravel ==> 细砾,细砾石 | fine grinder ==> 细研磨机