天然砂是岩石风化成的岩石颗粒,是由自然条件作用(主要是岩石风化)而形成的,粒径在5mm以下的岩石颗粒,包括天然海沙、湖沙、河沙或碎石砂(即矿物天然分裂为细小的砂粒)。天然砂是做建筑、混凝土、筑路材料、[详细]
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