Diamond Culet: All You Need to Know

Introduction

Diamonds are known for their uniqueness and exquisite beauty. One important aspect of a diamond’s structure that greatly influences its appearance is the culet. In this article, we will explore the significance of the diamond culet and what you should consider when purchasing diamonds.

What Is a Diamond Culet?

The culet, pronounced as ˈkyü-lət, refers to the tiny pointed area at the bottom of a diamond where the facets meet the pavilion. Essentially, it is the bottom tip or point of a diamond.

A diamond can either have a pointed culet, indicated as “none” on grading reports, or an additional rough or polished facet that runs parallel to the diamond’s table. The presence of a culet adds to the total number of facets on a diamond. For example, a round brilliant cut diamond may have either 57 or 58 facets, with 57 facets indicating the absence of a culet and 58 facets featuring a faceted culet.

In the past, large culets were common in diamonds. Old mine and old European cut diamonds were particularly known for their prominent culets. However, today, large culets are considered undesirable as they allow light to escape through the bottom of the diamond, negatively impacting its fire, brilliance, and overall beauty.

Diamond Culet Grades

The size of a culet is described using an 8-grade system established by the Gemological Institute of America (GIA). These grades include None, Very Small, Small, Medium, Slightly Large, Large, Very Large, and Extremely Large.

When a loose diamond is sent for certification, a gemologist will typically measure the culet’s size using non-contact optical measuring devices or a gemological microscope. The face-up view allows for the measurement of the culet’s size, while the side view helps determine its angle.

The size of the culet, ranging from Small to Extremely Large, can also be expressed as a percentage relative to the average diameter of the diamond, typically measuring from approximately 1.5% to 15%.

The Impact of Culet on a Diamond

The presence or absence of a culet is a topic of debate among jewelers, with arguments both for and against its inclusion. The primary purpose of a culet is to protect the pointed end of the diamond from damage. While diamonds are incredibly durable, the pointed tip is vulnerable to cracking or breaking upon impact.

From a light performance and appearance perspective, large culets can be visible through the table of a diamond, appearing as dark circles, and allowing light to escape through the bottom. This adversely affects the stone’s sparkle and brilliance.

Modern cutting standards lean towards the absence of a culet, but it’s important to note that a pointed culet can be easily damaged, particularly during the diamond’s mounting process. In fact, the culet is the most vulnerable part of a diamond. Therefore, it is crucial to secure the stone in a protective setting to minimize any potential risks.

If you prefer a diamond with a faceted culet, it is advisable to opt for Very Small or Small grades as they fall within the “Excellent” range. Larger culets can significantly impact the appearance of the stone, especially in the case of larger diamonds, where they may appear as dark circles.

In summary, when considering the culet of a diamond, it is essential to strike a balance between protecting the stone and maximizing its visual appeal. Whether you choose a diamond with or without a culet, always ensure that it is set securely to safeguard its longevity and overall beauty.

Featured image: Mark S Johnson / Shutterstock