the lower reaches of Suijiang River
Huangtian, Guangning-xian, Guangdong-sheng, China

This is a sample of building material for exportation to Japan.  It is sand/gravel with various size of grain.  The grains are 6.0mm or less in diameter, and they are sub-angular.  Most of them are fragments of quartz or feldspar, and there are a little pieces of sandstone or crystalline schist.