Natural vs Treated
Note: This post is referring to color-enhancing treatments which is different than a clarity-enhanced diamond
Natural colored diamonds are among the rarest gemstones found on Earth. With all the amazing properties of diamonds, plus a wide variety of beautiful colors, they are truly an extraordinary gemstone.
I’m sure you’ve seen colored diamonds before, but did you know that diamonds exist in 10 different colors? Actually, over 300 different colors have been identified but let’s stick with the basic colors you already know.
A list of the colored diamonds in order of their rarity (least rare at the top):
Natural colored diamonds (aside from yellow and brown diamonds) are all much more expensive than colorless diamonds.
For example, a 1/2 ct Round Natural Blue Diamond could cost upwards of $80,000 versus the same colorless diamond for about $2,500.
Most of the colored diamonds you see in jewelry stores are stones that have been treated to enhance their color. This helps keep their cost affordable. On a side note, treated pink diamonds are still expensive because white diamonds rarely turn pink with radiation or heat treatment.
There’s nothing wrong with a treated diamond as long as the treatment is legitimate. The color is permanent and the stone remains durable.
Safe Types of Treatment
The two most common types of color treatment are irradiation and HPHT (high pressure, high temperature). Both of these methods are safe and result in a permanent change (the color will not fade).
Irradiation is the most common form of color treatment. Make sure to get a diamond that was treated within the U.S. In the U.S. there are laws in place that require the manufacturer to use a specific type of irradiation (with alpha rays). Many overseas companies (where there are no regulations) will use a cheaper process with gamma rays – leaving the stone radioactive after the process. I won’t take the time here to explain why wearing a radioactive gemstone right next to your heart would be a bad thing.
The HPHT method uses an enormous amount of pressure and high temperatures to expunge the natural color that was already in the diamond. It’s much harder to control the color of the diamond with this type of treatment.
Avoid Diamonds With Surface Coating Treatment
Colored diamonds with surface coating treatment are a bad deal. First of all, the coating can wear off. The other problem is that you have to remove this type of stone from a ring or pendant in order to do the most basic jewelry repairs. This includes (but not limited to) rhodium plating, prong re-tipping with a flame, or even cleaning the ring in an ultrasonic.