Here's the latest article from the Jewelry Collecting site at BellaOnline.com.

Gemstones - GIA Grading Systems
In our continuing series of articles about gemstones, we explore the three key charts in the GIA Type Colored Stone Grading System, the Color, Tone and Saturation scales. Understanding how to grade gemstones is a helpful tool when purchasing gemstone jewelry.

http://www.bellaonline.com/articles/art42397.asp

Susan
Jewelry Collecting Editor
http://JewelryCollecting.bellaonline.com