Reference work entry
This is a granite landscape with rounded shapes like eggs. It is a product of spherical weathering of granite, especially at locations with columnar joints and conjugate joint sets, and they usually form on the weathered surface above the weathered granite crust. When a well-jointed granite body erodes and falls from a granite peak, wall or pillar, the original angular rock experiences physical and chemical weathering, which causes the rock surface layers to peel off and rounds the rock surface until irregular spheroids remain, which are called granite bullions. Granite bullions are smooth and easy to roll, and they will easily scatter on the ground when the landform is flat, subsequently look like residual stone eggs on the planation surface. In mountainous areas, these bullions tend to roll downhills and pile up in the foothills and valleys (Fig. 23).
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