Gem select; refractive index chart; dec. 2007, Refractive index chart. refractive index, or ri as it is often abbreviated, is one of the most important signatures of a gemstone. measuring the refractive index is. Pearl reports & services - gemological institute america, 11111pearl identification report pearl identification report. details quantity, weight, size, shape, color, origin, mollusk, environment and detectable. Rocks, gems minerals – gem guides book , 2 rocks, gems, and minerals (a falcon guide), romaine. an accessible field guide to 80 of the most common and sought-after rocks, gems and minerals in north america.
Gemstones information gem pictures - bernardine, Gemstones information gem pictures stone fossil gemstone chart chart gemstones pictures description stones.. http://www.bernardine.com/gemstones/gemstones.htm International gem society igs - information , Gem learning center. hundreds free articles science, identification techniques gemology.. https://www.gemsociety.org/ Specific gravity chart - gemselect, Specific gravity chart. specific gravity express relative density gemstone. measured ratio density gemstone . http://www.gemselect.com/gem-info/specific-gravity.php