Beyond the 4C’s

By Robert Underhill

Traditional diamond grading, known to most as the 4C’s, is familiar to all. Most consumers searching for diamond pricing have viewed a diamond chart depicting the characteristics that are associated with a diamond’s quality. Diamond clarity, diamond color, and diamond cut are known to most. What many consumers don’t realize are how many variables lie beyond the 4 Cs.

Diamond Fluorescence

One of the phenomena a diamond can exhibit is fluorescence. Fluorescence in a diamond can be detected by using a black light. When viewed under a black light, fluorescence in diamonds will glow with varying intensities and varying colors. Although diamond florescence does not impact the 4C’s of diamond grading, it can affect the value and appearance of your diamond. Diamonds that have higher grades of D through H can be significantly lower in value if they exhibit strong fluorescence, since this will detract from the appearance of the stone. Diamonds with lower grades J and below are often more attractive if they have a strong blue florescence.

Enhanced Diamonds

Diamonds are subject to many different types of treatment that effect their color and clarity. The accepted standard is that any process that alters the natural characteristics of the diamond should be disclosed to the consumer. It is virtually impossible for traditional diamond grading standards to be applied to stones with altered clarity.

Diamond Laser Treatments

One common treatment is laser drilling. Lasers can be used to bore small tunnels into a diamond to burn dark, undesirable inclusions from the stone. The vented areas can then be treated with acid to whiten the areas, which were formerly occupied by carbon.

This process should be disclosed to the consumer. However, many consumers are unaware that this modification was made to their diamond. Laser drilling is detectable under magnification and usually does not compromise the durability of the stone or change the stones appearance over time.
Note: This process should not be confused with laser inscribing a stone’s girdle with a serial number or message, which is an acceptable practice.

Diamond Fracture Filling

The most common clarity enhancement today is fracture filling. In this process, vented inclusions and fractures are filled with a foreign material that is cured or hardened in the stone. Once the fractures are filled, the diamond appears to have fewer or less noticeable flaws.