The purpose of this article is to educate consumers about the benefits of certified diamonds compared to lesser quality treated diamonds.
Most consumers are not aware that diamonds can be treated to improve their clarity, color or both. These treatments are applied to lesser quality diamonds, because it improves their appearance and marketability. Unfortunately, it also means that customers can pay too much for a diamond if an unscrupulous salesperson fails to disclose the treatments. To the contrary, certified diamonds are sold in their natural, polished and untreated state. If the Gemological Institute of America (the most respected independent laboratory that grades and certifies diamonds) suspects that a diamond is treated, it will not provide a certification.
Treated diamonds are illusory. They may look good, but you really don’t know the quality of diamond you are getting, and the degree of treatment that was applied to the diamond. Some of the treatments can be removed by wear and repair, thereby revealing the diamonds lower quality and less attractive appearance. An honorable jeweler (most are) will acquaint you with the fact that a diamond is treated, but may not know the actual degree of treatment applied to the diamond. You will become aware of the impact of excessive treatment as we discuss the various treatments and their limitations.
Kinds of Treatment
Laser beams can be used to penetrate a diamond and vaporize any imperfections, such as inclusions (dark mineral deposits) that exist. This process will improve clarity, but will leave hollow laser channels that must be filled with resins and glass hardening substances. Depending on the degree of treatment, these channels may or may not be seen with the naked eye. A competent jeweler or appraiser will see this treatment and will devalue the diamond and appropriately lower the price.
Many polished diamonds have minute fissures or fractures that penetrate into the diamond from the surface and adversely impact clarity. The same, or similar, resins and glass hardening substances that were used to fill laser channels are used to fill these fissures. These treated fissures are normally seen with the aid of a jeweler’s loupe or microscope, but a “flashing” effect can also be seen with the naked eye, if the diamond required extensive treatment.
Problems with Laser Drilling and Fracture Filling
A consumer needs to know if these treatments were applied to a diamond, because exposure to harsh chemicals and extreme heat, such as a jeweler’s torch (when repairs are made to the setting) can remove the filling from the channels and fissures, thereby returning the diamond to its untreated state.
High Pressure-High Temperature (HPHT)
Exposing a diamond to HPHT can alter its color. HPHT can be used to remove the brown or yellow tints from white diamonds to make them more colorless, or intensify the color of fancy colored diamonds, such as yellow, pink, blue and black diamonds. Fortunately, the color change is permanent. Unfortunately, the value of the treated diamond is less than a natural diamond of the same color.
Bombarding diamonds that have certain innate color properties with atomic particles can improve the color. This treatment has been successfully used to enhance the color of green diamonds, in particular. The treated diamonds do become radioactive, but the radioactivity is very low and within acceptable ranges prescribed by the US government. This treatment does produce a permanent color change, but like HPHT treated diamonds, they are lower in price and value than natural colored diamonds.
Government Requirements on Color Enhanced Diamonds
The Federal Trade Commission requires that all colored diamonds that are enhanced by treatment be disclosed to consumers. Recent legislation requires that color treated diamonds have a disclosing inscription on the girdle of the diamond to avoid misrepresentation.
You can avoid all of these issues and concerns by simply buying a diamond certified by the GIA. If you want to buy a treated diamond, you should expect to pay a sharply reduced price.
This article is a continuation of efforts to encourage consumers to buy diamonds that have been graded for quality and certified by the Gemological Institute of America. They cost more, but at least consumers know what they are buying. For valuable information on certified diamonds, read the article entitled “What Does Certification Really Mean?”
The Author: Paul Buchanan is a Graduate Gemologist, Graduate of the American Institute of Diamond Cutting and President of Bella Ideale Diamond Consulting Services. You are invited to comment on this article by contacting Paul Buchanan at email@example.com or calling 855-261-0100 (Toll Free).