Peridot: Peridot is rich in magnesium and has an iron content that gives the gem its green coloring. The shades of Peridot range from yellow-green to olive green and dark green. Peridot was called "the gem of the sun" by the Egyptians, and this super bright gem is a symbol of positive energy, happiness, and creativity. Drawing upon its link to the sun and the summer month of August, peridot is known as a bringer of light and good vibes.