Gemological Science Intl.
GSI provides gemstone identification, grading & testing services, research & educational programs to the diamonds, gemstone & jewelry trade.
www.gemscience.net
For more information please visit: https://www.instagram.com/gemscienceinternational/
Useful links:
➥ GSI
➥ Gemological Science International
➥ GSI vs. GIA
➥ GSI certified
➥ GSI certificate