When it comes to the perfect diamond, all the light which enters a table will reflect. This creates the sparkle that diamonds are famous for; however, not every diamond is perfect. When a diamond has light which does not reflect back, it creates dark spots in the stone. In many cases, the light leaks out the bottom of the stone. While this is the most common occurrence, it is not the only way that a diamond can appear dark. For example, fancy cut stones such as oval shaped, marquise cut, or pear shaped diamonds can have a bow tie effect. The name refers to what appears to the eye which is a dark bowtie across the diamond. Even though there is darkness, it is not from light leaking.
What Causes The Bowtie Effect?
The most important aspect in determine the quality and value of a diamond is the diamond’s cut. This refers to the consistency of proper proportions of the diamond’s many facets. In the event that a diamond is poorly cut, light will not properly reflect from the diamond. In many cases, this is caused by light leakage. However, the bowtie effect is actually caused by another problem: obstruction.
Instead of the normal scenario of light entering the diamond and exiting elsewhere, bowties are the result of light being shielded from entering the diamond. Although diamonds would normally sparkle from all angles, diamonds experiencing the bowtie effect result from direct light being blocked from entering the stone in the first place.
Diamond Cut and Diamond Bowties
The higher quality the diamond cut, the less likely the chance of bow ties being visible. However, simply picking a better cut will not completely eliminate a bowtie. Skilled diamond cutters will be able to minimize their appearance, but ultimately a diamond may still appear to have the bowtie effect for another reason. One example is the amount of polishing done on fancy cut diamonds. In this case, polishing may remove too much of the overall carat weight from the rough diamond. This will cause even a skilled diamond cutter to choose a bowtie effect over creating a smaller diamond. Overall, though, the higher quality diamond cut results in fewer bowties. This is important when buying diamonds online as it may be difficult to spot a bowtie without knowing what it is.
Are Diamond Bowties Flaws?
Although diamond bowties are widely considered to be a net negative, they're not always a bad flaw. The diamond bowties to avoid are large enough to create black areas throughout the entirety of a diamond. However, in some fancy shaped stones, the bowtie effect helps better define a diamond. This character boost is more akin to a beauty mark than anything else. However, if a diamond displays an obvious bowtie effect and has a poorly rated cut, then beware. These are often signs of a diamond with more flaws than perks.
Learn more about diamonds in our Diamond Education center!