The color of the Major Stone Forest is light grey, but the color of the Naigu Stone Forest is dark grey. The reason is primarily because they are formed from different rocks. The rock of the Major Stone Forest is pure limestone composed mainly of calcite (rich in calcium). While the rock of the Naigu Stone Forest is dolomitic limestone and siliceous limestone composed of, besides calcite, dolomite (rich in magnesium) and chert (rich in silicon). Being weathered, different rock presents different color. In addition, the colonization of lichen on the rock surface also darkened the rock.