Sea sand of Hon Island, Marugame-city, Kagawa, Japan

This is coarse sand (1.0mm or less in diameter) with skeletal grains of various marine life remains (4.0mm or less in diameter).  This sand was picked up in Setonaikai Sea as aggregate for concrete (prohibited from picking at April 2005).  It consists of quartz, feldspar, sandstone, shale, seashells and so on.