Welcome to the ISG Global Network Gemstone Reference Library. This library currently offers information and photographs on over 60 gemstones and gem materials. This area will be constantly under construction as we strive to bring you the most up-to-date information on gemstone market developments. In the information pages you will find a combination of consumer information, gemstone background information, and gemological information to help you identify and grade these amazing gems. If there is a gemstone you need information on and do not see it listed here…please let us know. We will research and add that gemstone. Remember, this is your ISG Global Network and we are here to assist you in any way possible. Thank you for being a part of the ISG Global Network.