If you have ever bought a diamond, youknow that it is one of the most expensiveand important investments you will makein life, next to a home, education, or vehicle.The Gemological Institute of America(GIA), considered the world's foremostauthority on gemstone grading and reporting,ensures the public's trust by authenticatingdiamonds. Established in 1931, GIAcreated the four C's—color, clarity, cut, andcarat—to determine a diamond's value.But cracks have appeared in the organization'sfoundation, which grades 1 millionstones a year. In October 2005, the GIAfired four employees after an April lawsuitalleged diamond upgrading after $15 millionof stones appraised for far less. A 4-month internal investigation found briberybetween the lab workers and a handful ofdiamond dealers. According to the , the GIA maintains that theunscrupulous dealings affected only asmall number of stones, although it willnot disclose which diamonds may havephony ratings. Anyone who questions theirdiamond's value can send their loose stoneand its accompanying certificate to theGIA for recertification at no charge for alimited time. For more information, contactthe GIA at 800-421-7250, or visit theirWeb site at www.gia.org.