GEMS Desautels, Paul E. Gems in the Smithsonian. Smithsonian Institution Press, 1972
GEMS Desautels, Paul E. The gem kingdom. Random House, 1970
GEMS Greenbaum, Walter W. The gemstone identifier. Prentice-Hall, 1988
GEMS Matlins, Antoinette Colored gemstones: the buying guide. Gemstone, 2001