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IGI provides independent grading reports, colored stone reports, identification and appraisal reports, diamond authentication and attestations of origin, and laser inscription services. They also offers diamond and colored stone courses through IGI's Schools of Gemology. [7] Graduates from the IGI school of Gemology are awarded an IGI Diploma.
A 2010 effort led by State Senator Gloria J. Romero, a Democrat from Los Angeles, sought to remove serpentine from its perch as the state's official stone. Organizations such as the Asbestos Disease Awareness Organization have supported the move as the olive green rock is a source of chrysotile , a form of asbestos that can cause mesothelioma ...
The Richard T. Liddicoat Gemological Library and Information Center, located at GIA's headquarters in Carlsbad, California has a collection of 38,000 books, 700 international magazines and journals, 1,000 videos/DVDs, 80,000 digital images, 300 maps, and approximately 6,000 original jewelry design renderings.
The following is a list of rock types recognized by geologists.There is no agreed number of specific types of rock. Any unique combination of chemical composition, mineralogy, grain size, texture, or other distinguishing characteristics can describe a rock type.
Jet is a type of lignite, [1] the lowest rank of coal, and is a gemstone.Unlike many gemstones, jet is not a mineral, but is rather a mineraloid. [2] It is derived from wood that has changed under extreme pressure.
Bannerstones are artifacts usually found in the Eastern United States that are characterized by a centered hole in a symmetrically shaped carved or ground stone. The holes are typically 1 ⁄ 4" to 3 ⁄ 4" in diameter and extend through a raised portion centered in the stone. They usually are bored all the way through but some have been found ...
A gemstone (also called a fine gem, jewel, precious stone, semiprecious stone, or simply gem) is a piece of mineral crystal which, when cut or polished, is used to make jewelry or other adornments.
The Ica stones are engraved with various types of images. Some images are directly incised whereas others have been made by removing the background, leaving the image in relief . The images vary from simple pictures on one side of a pebble to designs of great complexity.