Thermoplastics, in basic terms, are melt-processable plastics (materials that are processed with heat). When enough heat is added to bring the temperature of the plastic above its melt point, the plastic liquefies (softens enough to be processed).
In the U.S., diamonds have been found in Arkansas, Colorado, Wyoming, and Montana. In 2004, the discovery of a microscopic diamond in the U.S. led to the January 2008 bulk-sampling of kimberlite pipes in a remote part of Montana.
Miners unearth world's biggest diamond. The world's biggest diamond, believed to be twice the size of the Cullinan, has been discovered in the North-West Province of South Africa. The find has electrified the diamond community, but the circumstances of the discovery are shrouded in mystery.