Where a diamond consists of one element only, a gemstone is a compound – it consists of two or more elements.
Gemstones are graded differently than diamonds.
You can hardly find two identical gemstones. So, in order to maintain a uniform system of judging and grading stones, GIA has made a colored stone grading scheme.
Gemstones are graded in color, clarity, carat and cut, but the most important factor, by far, is color.
Let’s talk about color – because color is king.
Color
If the color is exceptional, the clarity and cut are not as important.Many times you will see that colored stones are cut in what we call native cuts. In native cuts, the gem cutter has spent a lot of time getting the best color out of the stone.Let me explain a bit:Color is judged in 3 different ways:
- Hue is the first impression of a stone’s color, which is the body color of the stone. Hue tells the color of the stone, and whether it has a trace of another color.
- Normally, we prefer stones with a pure color. However, it depends on the stone.
- Tone is the darkness or lightness of the color, which is graded from very light to very dark. The most valuable stones will be medium light, medium, and medium dark.
- Saturation is the color’s strength or intensity. It determines how much color the stone holds. The finest saturations will be judged as moderately strong, strong or vivid, with the latter being most valuable.
Cut
A colored gemstone is cut differently from a diamond.
When cutting colored stones, the gem cutter tries to retain as much weight as possible, but the main focus is on how to get the optimal color out of each gemstone.