Gravel smaller than Sand is called fine sand. Fine sand is usually easily found on the beach and in the river. In civil engineering, according to the classification, ASTM called fine sand for gravels smaller than 4.75 mm and coarser than 0.075 mm of. 

According to the Unified Soil Classification Standard, sand is classified into three categories: fine, medium and coarse. In slang, gravel is smaller than sand and coarser than sand. Sand is usually easily found on the beach and in the river. In civil engineering, according to ASTM classification, aggregates smaller than 75 mm and larger than 4.75 mm are called sand. 

According to the standard classification of uniform soil, sand is divided into two categories: fine sand and coarse sand. Solid soil particles are called sand if their diameter is between 0.50 and 2 mm. Sand is in very commonly use in construction, often providing bulk, strength and stability to other Construction materials such as asphalt, concrete, mortar, render, cement, and screed.

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