There is nothing wrong with enhanced and treated loose diamonds, so long as you are made aware of it to begin with. If you choose to purchase a treated diamond, you will save money and it will look pretty nice. However, the problem comes in when enhanced loose diamonds are sold without being clearly marked. Diamond treatments can be difficult if not impossible to detect with the naked eye, and they have a huge effect on diamond price.
In a retail store, especially when diamonds are already in a setting, it can be difficult to make an accurate determination of a diamonds grades and measurements. If there isn't a certificate, it is almost impossible. Having the proper certification from a reputable lab like GIA also has the benefit ensuring that your diamond isn't enhanced, treated, or altered in any way. A certificate is the single greatest tool for consumers of diamonds and diamond jewelry.
We don't recommend enhanced and treated loose diamonds of any type. If your going to be investing the money into a loose diamond or engagement ring, it makes sense to get a quality that you can be proud of. You might save some money with an enhanced or treated loose diamond, but the allure of the diamonds natural beauty and its lasting value will be lost. Your going to be keeping your loose diamond for a long time, make sure you make the right choice the first time
Clarity Enhancements & Treatments
A real life laser is used to bore a tiny hole into a diamond to get access to an unsightly inclusion. Once the hole is made, techniques can be used to remove or bleach the inclusion. This can be used to remove black inclusions, the most noticeable, or crystals and other less prominent inclusions. Unfortunately, the tiny hole is left behind. Fortunately, a laser drilled diamond is easily detectable under magnification
Fracture, cleavages, or cracks are breaks in the diamond. They can be a natural part of the stone or introduced during the cutting and polishing. Glass is used to fill the cracks to reduce their appearance, which would otherwise severely affect its value. There are many techniques to identify a fracture filled stone and they are best avoided. Most people, if asked, would not want cracks or fractures in their precious diamond.
Color Enhancements & Treatments
Utilizing a chemical or plastic solution, a diamond can be coated to improve the color or add color. This technique is usually easier to detect, and is almost always undesirable.
The coating can usually be removed by boiling in an acid, but this should only be attempted by professionals.
While this is usually used to improve color by approximately one grade, diamonds have been coated in different colors, notably pink. Watch out for this treatment, and know that certificates are not issued for diamonds with this treatment.
Irradiation utilizes radiation to create a color change in the diamond.
This treatment usually produces a diamond of a color other than white, usually greenish, bluish, or black. They can be further annealed, or heated up and cooled slowly, to modify them into an appealing pink, yellow, or orange. On the plus side, the change is permanent and detectable by a reputable gemologist.Fancy color diamonds are significantly more expensive, particularly pink and yellow, so make sure that the fancy color diamond you have your eye on isn't a case of mistaken identity.
HPHT–High Pressure, High Temperature
This process, which mimics the diamonds formation in the earth, is most often used to turn a very particular type of brownish diamond lighter and whiter.
While it requires a trained gemologist using specialized equipment to detect, most HPHT color enhanced diamonds will have certificates that clearly label them as treated. Only a very small percentage of diamonds, around 1%, are candidates for this treatment. The diamond type, called IIa, is usually of very high quality in both color and clarity, but a fluke causes a portion of type IIa diamonds to exhibit the color that HPHT can fix.
They aren't the most common, so you may not ever run into them, but if you do it will be clearly marked on a GIA certificate.