Gems found most often in volcanic regions, particularly in areas where rivers of volcanic being; as certain kinds of precious stones made up in the ground and at different depths, and can be gems are in layers of earth near the surface, and this means it is possible to be present at a depth of 160 meters, and go out to the surface of the earth in the event of volcanoes, earthquakes, such as rubies, diamonds and emeralds. These precious stones found in nature alone free, as the gems found in the depths of the seas and oceans, such as pearls and coral, and some are left above the ground as a result of the plant kingdom such as yellow amber.
