A Gem of A Story Online is the Web component to a live, interactive, televised field trip to the Janet Annenberg Hooker Hall of Geology, Gems, and Minerals at the Smithsonian National Museum of Natural History in Washington, D.C. The site offers a "virtual tour" through the Smithsonian exhibits, educational activities, online archives, and resources.

The Web site of The American Gem Society (AGS), like the society itself, offers information to protect consumers interested in purchasing gems. Learn the basics of buying a diamond, starting with the "4-C's." Individual questions can be emailed to AGS representatives via the Martha Stewart Web site (MarthaStewart.com).

This gallery of color photographs taken of precious gems and metals through an optical microscope showcases the beauty of these items' molecular structures.

Read a profile of a gemologist along with descriptions of how some beautiful jewelry pieces were constructed to gain a better understanding of the modern professional world of gems.

Read the story of the dazzling Hope Diamond, a premier attraction of the Smithsonian Institution since 1957.

The United States Geological Survey offers introductions to gemstones found in the United States. Included are sections on garnets, opals, pearls, sapphires, and turquoise.

Learn more about the geology of gems at this site, which also includes information on the National Meteorite Collection, and the National Rock and Ore Collection.

View images and read descriptions of several specimens from the Smithsonian's extensive collection.

This highly readable book chronicles the long and checkered history of the pioneers of synthetic diamond-making. The mad Swedish inventor Baltzar von Platen and the irrepressible American scientist George Kennedy are just two of the many brilliant characters whose stories are told here with flair and an eye for eccentricity. See our excerpt, "The Science Behind the Sparkle."

Published in association with the American Museum of Natural History, where Harlow is a scientist and curator of gems and minerals, this is a coffee-table-sized yet authoritative book of essays by leading geologists, gemologists, physicists, and others. Beautifully illustrated with photographs and artwork.

The massive fifth edition of this classic work begins with a description of diamond and moves onto other gems and ways to identify them, including measuring their hardness, optical effects, and specific gravity, among other methods.