Excellent clarity is one of the most prized attributes in a diamond, hiking up values dramatically as clarity grade improves. Not surprisingly, the demand for high clarity diamonds has led to treatments designed to change and enhance this attribute. One such treatment is laser drilling, a hotly debated technique that has both advantages and drawbacks for buyers to consider.
Laser drilling is a technique used to enhance the appearance of diamonds by removing internal flaws. While it can improve clarity, it may also affect the durability and value of the diamond.
The question around whether laser drilled diamonds should be avoided is not a simple yes or no. There are persuasive arguments on both sides of the debate. This article will provide an overview of laser drilling, its potential benefits and risks, things to watch out for, and advice for making an informed purchase.
How Does Laser Drilling Work?
Laser drilling is a process by which lasers are used to target and remove internal flaws or inclusions in a diamond. A focused laser beam is aimed at dark inclusions within the stone, essentially burning a hole or tunnel from the surface down to the inclusion. This channel then provides access to the inclusion, which can be burned away by the laser beam or dissolved using acid.
The resulting tunnels are minute, generally measuring less than 0.2 millimeters in diameter. In fact, they are typically so small that they can only be observed under 10X magnification. The channels created by laser drilling are subsequently filled to disguise signs of the treatment—more on that later.
Lasers allow gem cutters to drill into a diamond horizontally, from the side, or vertically, down from the table facet. This grants access to inclusions located below the surface of the stone that would have been impossible to reach otherwise.
Essentially, laser drilling serves the same purpose as the more traditional clarity treatment of diamond sawing. However, lasers offer more precision and leave smaller tunnels compared to diamond sawing.
Why Use Laser Drilling?
The goal of treatments like laser drilling is, not surprisingly, to improve the clarity grade of a diamond. The better the clarity, the higher the gem’s value. Flaws negatively impact the appearance of a diamond and how light travels through it. By removing or reducing the number of inclusions, laser drilling can increase a diamond’s visual appeal.
Minor inclusions that cluster together have a stronger impact on clarity grade compared to isolated flaws. Laser drilling is commonly used to break up these clustered inclusions. Separating a group of small inclusions into individual ones can make them less noticeable and move a diamond into an improved clarity grade.
Laser drilling also allows gem cutters to salvage diamonds with significant internal flaws or fractures that would have otherwise been unsellable or fit only for industrial uses. By carefully targeting the inclusions to avoid causing further damage, laser drilling gives new life to stones downgraded due to their natural internal characteristics. The technique also avoids the significant weight loss associated with sawing off entire areas of a diamond.
Potential Downsides of Laser Drilled Diamonds
As with any diamond treatment, there are several risks and drawbacks associated with laser drilling that buyers need to understand:
Durability and Structural Integrity: Drilling microscopic holes through a diamond does unavoidably impact its durability. The tunnels are areas of weakness that reduce the structural integrity of the stone. Diamonds are split into different grades based on overall cut quality, with ratios between depth percentage, table size, girdle thickness and more affecting its resistance to impact. Laser drilling alters this careful balance. The holes also make it easier for new fractures and cleavage planes to form within the gem.
Re-filling Drill Holes: To hide signs of laser drilling, the tunnels are commonly filled with a glass-like substance. This filling material can work its way back up towards the surface or fall out over time. The pathway may then need to be re-filled to avoid visibility. If done poorly, poor-quality filler leads to clouds and new inclusions around tunnels.
Detection: Modern laser drilling techniques are extremely sophisticated, making it very difficult to identify treatment, even under magnification. Labs still uncovering laser drilled diamonds misrepresented as untreated indicates there is ongoing risk. Specialized equipment like fiber-optic lighting combined with microscopy is generally required. Tunnels hidden under facets are obviously impossible to detect without removing and re-cutting the stone.
Value Reduction: Once identified, most laser drilled diamonds undergo a steep discount compared to their untreated equivalents, generally in the range of 15 to 25 percent. Value is ultimately tied to consumer demand. Many buyers prefer completely natural, untreated stones and are wary of treatments like drilling that alter the fundamental composition of the diamond. Disclosure is critical; undisclosed laser drilling leads to even steeper value reductions if eventually detected.
Skill Required: Laser drilling diamonds requires specialized expertise and very expensive equipment. Done poorly, the tunnels can be unsightly, negatively altering reflection and sparkle. Modern laser techniques reduce visibility, but buying from disreputable or inexpert vendors comes with risks.
Advice for Buyers on Laser Drilled Diamonds
Some buyers strictly want untouched natural diamonds and are wary of any treatments. Others are open to treatments as long as durability is not overly compromised and there is full disclosure.
Regardless of your perspective, there are several recommendations for making an informed purchase:
– Seek diamonds graded by reputable gemological laboratories like GIA or AGS that clearly state on the certificate if laser drilling was used. Never rely solely on a seller’s word.
– Work with jewelers and vendors that fully disclose any treatments and provide certification. A vendor that does not mention laser drilling upfront may be best avoided.
– Take time to inspect the diamond carefully yourself for signs of drilling, even if certified. Some tunnels can be incredibly difficult to detect, but it is wise to verify.
– Consider the location and type of inclusions drilled. Surface-reaching drilling on the table or crown facets is more visible. Drilling directly alongside fractures can weaken the stone.
– Keep in mind that laser drilling does not automatically mean a poor quality diamond. In some cases, it is only detectable under microscopic inspection. Make decisions based on your individual comfort level.
– Be aware of diamond simulants like moissanite that can appear superficially similar to laser drilled diamonds. Rely on expert gemologists for detection and identification.
There is an understandable wariness around any diamond treatment given the gem’s reputation as a rare embodiment of pure crystalline perfection. Laser drilling represents a dramatic intervention compared to other clarity enhancements like fracture filling. However, in the right circumstances, handled with care and expertise, it can offer an otherwise unusable diamond a second life.
Common Questions About Laser Drilled Diamonds
Does laser drilling damage or weaken the diamond?
Laser drilling does unavoidably impact the structural integrity of a diamond. The channels and tunnels required to reach inclusions represent points of weakness where fractures and cleaving may propagate from over time, especially if exposed to hard knocks or blows. However, modern laser techniques minimize the diameter required for drilling, and when inclusions are carefully targeted, the overall durability impact may be quite small in many cases. Still, minor damage is fundamentally intrinsic to the process.
Do laser drilled diamonds lose value compared to non-drilled diamonds?
Yes, diamonds confirmed to be laser drilled will undergo a reduction in value, generally in the range of 15 to 25 percent compared to an equivalent diamond guaranteed to be untreated. The value reduction stems from reduced consumer demand, wariness about durability, and resale risk. However, diamonds with undisclosed laser drilling usually face steeper price and value reductions if the treatment is detected later on down the line.
Can you tell if a diamond has been laser drilled by looking at it?
In most cases, the incredibly tiny tunnel diameters made possible by modern laser technology—as small as 0.2 millimeters—make drill holes impossible to identify with the naked eye, even under magnification. Sophisticated techniques involving fiber-optic lighting, magnification, and examination by a skilled professional gemologist are required for detection. Drill holes and tunnels may also be concealed under facets. It takes expertise and technology to reliably identify many laser drilled diamonds.
What are the risks of buying a laser drilled diamond?
The main risks are paying an inflated price due to non-disclosure of treatment, reduced durability and structural integrity compared to non-drilled diamonds, problems with fillers and re-filling of drill tunnels over time, and inability to recoup full value if reselling the stone. Using a trustworthy jeweler and getting a diamond certificate can help mitigate these risks.
Is a laser drilled diamond as durable as an untreated diamond?
In general, no. The laser drilling process does intrinsically weaken the diamond by piercing microscopic holes through it. However, modern techniques are quite sophisticated, with drilling done in the smallest diameters possible to reach inclusions. Targeting the drilling with precision to avoid existing fractures also limits damage. An expertly drilled diamond may suffer only minimal durability reduction in some cases. However, buyers should be aware that the drilling does impact durability to at least a small degree.
Should I avoid buying any diamond that has been laser drilled?
There is no blanket yes or no answer. Many buyers still prize completely untreated natural diamonds, want no compromises on durability, or are concerned about potential fracture issues over time.
Diamond treatments also make it harder to determine true value. For these buyers, avoiding laser drilled diamonds altogether makes sense. However, others may be fine with laser drilling done by experts as long as there is full disclosure and a lower price compared to equivalent untreated stones.