Pebbles is the incidental when mining yellow sand. And it gets its name because of the shape. As natural stone, pebble stone is taken from sand stone, which experienced the crustal movement millions of years ago. It was flushed by flood, textured and friction by running water. After a long time later, it is tormented by waves flush movement and is rubbed by gravel, then finally it is buried for millions of years. It may come into being because of the flood or debris flow. We can know the actual reason after searching for geologic structure, environment and the mountain around.
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