“Culet” is a word that sounds strange to most people. However, jewelers are pretty familiar with this term, and for good reason. It is one of the defining characteristics of a round-cut diamond, and depending on the circumstances, it can be important.
What Is a Culet?
In plain words, a culet is the facet at the bottom of a diamond. If you look at the stone from the side, you will see that the lower part of the diamond is cone-shaped (this part is also called “pavilion”). At the very end of that cone, you will find the culet – a small, flat surface, parallel to the top.

Culet is the facet at the pointed bottom of a diamond.
Do All Diamonds Have a Culet?
There are actually a lot of stones without a culet. This happens when the diamond cutter has simply decided not to make the bottom of the stone into a facet by polishing it and has instead left it sharp.
The reason some jewelers don’t create a culet has mostly to do with aesthetics – if you look at a diamond with a culet from above, this small bottom facet is visible from the top as a tiny point.
There is no such effect when the culet is missing.
The Culet Grading Scale
If you read a diamond’s certificate issued by the G.I.A. (Gemological Institute of America), you will see that there is a section that lists information about the culet.
The culet is described according to its size, and the G.I.A. uses the following grades: None, Very Small, Small, Medium, Slightly Large, Large, Very Large and Extremely Large.
Do I Need a Culet on My Diamond?
The main purpose of the culet is to protect the stone.
If the diamond’s bottom is sharp and the stone is accidentally hit, there is a greater risk of breaking off the pointed end.
There is a debate going on among jewelers about whether a diamond should have a culet at all, and there are arguments for and against it, so no uniform opinion exists.
In general, it is not fatal if your diamond doesn’t have a culet, but it is recommended to have a small one for additional protection, so you are free to decide for yourself what you prefer.
If you think you should have one, go with Very Small, Small or Medium if you are concerned about how the culet would change your diamond’s appearance.
If it is any larger, the culet will probably affect how the stone looks. This is especially true for a Very Large or an Extremely Large culet – you will definitely be able to see it from the top, and it will look like a dark dot.
If you decide to go with no culet anyway, be aware that extra care should be taken when the stone is set in its mounting.
In such a case, it is important that the diamond be put in a setting that will protect it well from outside stress.
Also, be especially careful when handling your diamond if it is loose.
Where to Buy Diamond Jewelry?
We recommend James Allen (read review) because you can see a 360-degree video for any diamond before buying it.
Blue Nile is another reputable diamond retailer we recommend.