Ask a Gemologist by mary l. harding, G.G.

I took my diamond engagement ring to be appraised and was told that the diamond was laser drilled. The jewelry store provided a gemological services report (enclosed) at the time of purchase and it does not say anything about laser drilling. What is laser drilling and how does it affect the value of the diamond?

Laser drilling is a permanent treatment used to improve the clarity of a diamond which is one of the four factors in determining value (the other three being carat weight, color and cut quality).

There are two schools of thought regarding laser drilling and determining clarity as a value factor:

The first is to determine what the clarity of the stone was prior to treatment (which requires the appraiser to make some assumptions about the nature of the inclusions enhanced) and include that determination when estimating the value.

The second is to determine the clarity of the diamond as it appears after the treatment with the belief that any addition in the value in improved clarity was acquired in the cost of laser drilling the stone. Because an appraisal should give as much information as possible in order to assist the reader in understanding how the valuation was estimated, I feel the most informative method is to give a range with the high clarity call being how the diamond appears after laser drilling and the low clarity call being what I feel, as a gemologist, the clarity was prior to laser drilling. Estimating the value is then based on an average of the two clarity calls, all other factors being equal. Additionally it is absolutely essential to disclose in the appraisal that the diamond has been laser drilled and give the reasoning behind the clarity range.

In regard to the documents you enclosed, I consulted the firm who prepared the document and was surprised to learn that he felt laser drilling didn’t need to be disclosed because it is an “enhancement” that doesn’t affect color and/or require special care. “Enhancement” is a term that became taboo in 1996 when the Federal Trade Commission revised guides for the jewelry industry, declaring use of the word led to deceptive and unfair trade practices. The word enhancement has been replaced with the word “treatment”.

Treatment is defined as any human-controlled process that improves the appearance, durability or value of a gem. By this definition some people in the industry feel cutting and polishing the gem must, therefore, also be a treatment. Cutting and polishing is a treatment the consumer can see. What the Federal Trade Commission is focusing on is the treatments that can’t be seen and they are trying to put regulations in place to be sure those are disclosed.

Laser drilling does not effect the durability of the diamond but the owner of a laser drilled diamond needs to know their diamond has received this type of treatment for three important reasons:

1) Heat from a jeweler’s torch during repair can damage a laser drilled diamond.

2) Perceived and actual value is affected.

3) Most importantly, it is the owner’s right to know.