Given the rarity and value of diamonds, it’s not surprising that some would seek ways to enhance or replicate their beauty. In recent years, diamond treatments, simulated diamonds,
and laboratory-grown or synthetic diamonds have become more common, more advanced, and harder to detect.
While treatments can increase a stone’s Color or Clarity, the presence of such enhancements may affect the diamond’s value – particularly if the price reflects its appearance after treatment.
Buyers have a right to know for certain whether a stone is natural, a diamond simulant or a diamond created in a lab, and whether or not the stone has been treated to enhance its appearance.
A GIA Diamond Grading Report provides buyers with the ultimate assurance that they’re getting exactly what they pay for.
Changing the Natural Essence of the Diamond
Diamond Color Enhancements
While many of these are not common in the market, GIA tests every diamond it grades for their presence.
Coating enhances a diamond’s color by masking an undesirable body color with an ultra-thin layer of chemicals or plastics. Another form of coating involves applying a thin film of synthetic diamond to the surface of a diamond simulant, giving it certain characteristics of a real diamond.
HPHT stands for a high-pressure, high-temperature. The process is an effective tool for changing the color of certain diamonds, making them colorless, pink, blue, green, yellowish green, or yellow. Outside of a well-equipped grading laboratory, this form of treatment is virtually undetectable.
There are two main techniques for improving a diamond’s clarity; laser drilling and fracture filling.
Laser drilling is commonly used to remove small dark inclusions. The laser bores a small hole into the diamond’s interior and burns away the inclusion, or creates a channel through which a bleaching agent can be introduced to improve the inclusion’s appearance.
Fracture filling hides white fractures in a diamond called “feathers.” A glass-like substance is injected into the fracture to make it less visible and to improve the stone’s apparent clarity. Because the filling may be damaged or removed during routine cleaning and repair, the technique is controversial. Good fracture filling is very subtle, and so examination by a skilled diamond grader is necessary to detect its presence in a stone.
How does a GIA Diamond Grading Report help you know whether your diamond has been treated?
GIA does not issue grading reports for any diamond that has undergone a treatment process that’s considered nonpermanent or unstable, such as coating or fracture filling.
GIA will issue reports for diamonds that have been laser drilled or HPHT processed, prominently disclosing these treatments on the report. As a further precaution, GIA also laser-inscribes the girdles of diamonds it identifies to be HPHT processed.
The Man Made Diamond
A synthetic diamond is man-made, the result of a technological process, as opposed to the geological process that creates natural diamonds. Synthetic diamonds have essentially the same chemical composition, crystal structure, optical, and physical properties of diamonds found in nature. Most synthetic diamonds are categorized as either high-pressure, high-temperature (HPHT) or chemical vapor deposition CVD diamonds, depending on the method of their production. Since HPHT and CVD diamonds are virtually identical to natural diamonds, differences only become clear when they are viewed by a trained grader in a gem laboratory.
While synthetic diamonds represent a small segment of the market, they are becoming more widespread and increasingly difficult to detect. GIA is at the forefront in meeting this challenge, offering a distinct report for synthetics so that there is no confusion in the marketplace.
How does a GIA Diamond Grading Report help you know if your diamond is natural or synthetic?
GIA tests every diamond to determine if it is natural. If a diamond is found to be laboratory-grown, GIA issues a Synthetic Diamond Grading Report, which looks distinctly different from the the standard grading report. As an added precaution, GIA also laser-inscribes the diamond’s girdle with a report number and a statement that the diamond has been laboratory-grown.
Common Diamond Simulants
While the appearance of diamond simulants is similar to that of natural diamonds, they are not diamonds. Common diamond simulants include glass and cubic zirconia (CZ), both of which are completely unrelated to diamond at the atomic level.
Simulants are, of course, less expensive than the real thing. They allow consumers to enjoy the flash and dazzle of diamond-like jewelry and to inexpensively compliment the latest fashion trend. But no matter how convincing the illusion, all diamond simulants have optical and physical characteristics that can be identified by a trained gemologist.
How does a GIA Diamond Grading Report help you know that your diamond is natural?
GIA tests every stone to verify that it is, in fact, diamond. GIA does not issue grading reports for simulants.