As a natural stone, pebbles are forming by millions of years of water flushing, extrusion, collision and sedimentation. Pebbles are usually smooth, but depending on how often they come into contact with the sea.
Pebbles can be found on the existing various beaches of oceans and inland areas once covered by ancient seas. When the oceans receded, landlocked countries form. Therefore, we can see the pebbles in rivers, lakes and ponds. In addition, the peebles can also form in the rivers, change never stops.
According to the location pebbles mined, it divided into beach pebbles and river pebbles, they are different in geological structure and appearance.
Beach pebble mostly smooth, round shape, and the size usually in 2-50mm, common colors are translucent white, yellow, brown, green, black.
The river pebbles are usually not as smooth as beach pebbles, owing to the gentler river current. Common colors are black, grey, green, brown, and white.