Diamonds

Diamonds come in many colors, though some are worth more than others. Common discolorations are yellow and brown, which is sometimes caused by nitrogen seeping into the crystal. Valuable colored diamonds such as pink and bright yellow are equally as celebrated as clear ones, though clear diamonds are glowing white because they are considered the purest form of the gemstone.

So how does the industry measure something like color? The Gemological Institute of America (GIA) created guidelines to grade diamond color that is used as an industry standard. This is done by comparing the color of graded diamonds to the color of control stones. These comparisons are done when the diamonds are loose, before they're set in any kind of jewelry piece, because the color diamonds in settings can be affected by the the golds or silvers used in the mountings.

Once the stones are examined, they are rated using a lettering system from D to Z. A D-graded diamond is extremely rare to find, because they are considered completely colorless. The rest of the ratings break down this way:

D-E-F: These are considered colorless.

G-H-I-J: These are considered nearly colorless.

K-L-M: These diamonds are faintly tinted, usually with a yellow-ish tone.

N-O-P-Q-R: Gems in this range are lightly tinted, visible to the naked eye.

S-T-U-V-W-X-Y-Z: These gems are the least valuable. They are tinted, usually yellow, but usually start to look a little brown.

A lot of times reports on diamonds will specify whether or not a diamond exhibits "fluorescence." This is tested by putting the diamond under the UV light, to see whether the diamond's color changes. Since UV radiation is a component of daylight and is also present in fluorescent-lit rooms, diamonds with this characteristic can appear to change color.

If you're wondering what it looks like here is a short summary: Diamonds that produce a blue reaction usually look white under the UV lighting condition. Stones that give off yellow may see an increase in intensity for the color.

If you have a stone that appears to be slightly discolored, minimize that by having it set on a higher mount, instead of embedded in something like gold. Setting it in a silver color such as white gold or platinum can help off-set the discoloration that might be visible to the naked eye when the stone is loose.