Parts of a Diamond: Table

Continuing our discussion of the parts of a diamond, or as some would characterise it, the anatomy of a diamond, we move to one of the most visually significant parts: the table.

As we noted in our study of the diamond crown, the term ‘part’ may seem confusing to some, as the diamond is one whole unit that is shaped out of a rough stone. However, the intricacy of the process and the various aspects of the stone that feature in the cut form is of great significance when it comes to its look, value and how it positions itself on a fine jewellery item like an engagement ring.

So in this Education page, we will be looking at the diamond table, analysing its significance, and what are the factors that contribute to a diamond that features an optimal table, and also how the look of the diamond table differs from two famous diamond cuts.

The Anatomy of a Diamond

As usual, we start this discussion with an overview of the key parts that make up a diamond’s final form. When speaking of the anatomy of a diamond the focus is on the intricate parts that make up the structure of the stone. One that is a function of its cut, faceting and shape.

Essentially the anatomy of a diamond only becomes a subject of discussion when we are talking about diamonds that are not in their rough or uncut form. In the gemstone and gemstone jewellery industry, the main consideration for fine jewellers and diamond cutters is to optimise the visual character of the stone: which in diamonds is greatly dependent on its cut. Whilst rough but polished diamonds are used on rare occasions the primary choice of the stone is the cut variant.

An important point about diamond cutting is that despite carbon-based gemstones (diamonds) coming in an array of natural shapes, sizes and colours (fancy coloured diamonds) when it comes to the art of lapidary follows certain fixed rules when it comes to the final structure of the cut stone. One that applies regardless of its shape (cushion, emerald or round) and type of faceting (brilliant or emerald cut) that is used.

The Main Parts or Components of a Cut Diamond:

The Table (Surface) is the centrepiece of the diamond that is visible when viewed from the top. The table is in fact a facet of the stone. The largest and is a key contributor to the diamond's clarity and sparkle.
The Crown is the area that surrounds the table of the stone that lies above the girdle. And it features star-shaped and bezel-shaped facets in the most popular brilliant cut diamond shapes.
The Girdle is the thin area that surrounds the diamond and connects the pavilion with the crown. It features no facets.
The Pavilion holds the largest surface area of the stone and lies below the girdle. The length and width of the pavilion greatly affect the diamond's light interactivity: from its reflection and retraction.
The Culet is the lowest point of the diamond. And it technically counts as an additional facet if it is shaped in such a manner. Otherwise, the culet is a pointed edge that aids the placement of the diamond and contributes to its ability to bend and shape light.

On this Education page, our focus is on the diamond table.

What is the Diamond Table?

To expand the point above the diamond’s table is the flat surface area at the top of the cut gemstone. The table of the diamond is actually a facet (i.e. a surface area of the stone that has been shaped in a map-like fashion). But since it is the largest and lies at the top of the stone and it greatly influences the overall shape of the stone it is viewed as a distinguished part.

When it comes to diamonds it is of great importance to get the table of the diamond right. The table, in addition to varying in its style depending on the diamond, greatly affects the clarity of the stone. Since is the region where much of the light that hits the stone enters is reflected from and is dispersed through and refracted within it. It is important to get the shaping of the table absolutely right.

Notable here is the clarity grade of the diamond stone. Diamonds with a high number of or larger inclusions are most visible through this region, thus affecting the final quality of the stone. When looking for diamonds with a large surface area, such as those found in an Asscher cut diamonds. However, the bigger table does not necessarily mean a brighter stone, as there is a payoff with the level of brilliance that the diamond exhibits, and there is some loss in the level of fire that the diamond showcases.

So this is a balancing game between the size of the table and the size of the crown. As too many tables will affect the brilliance and fire, a too small a diamond table on the other hand will allow less light into the stone.

Diamond’s Table Percentage

To get a bit into the subject. When it comes to diamond quality, the cut of the stone is considered to be one of, if not the most important factor. And the quality of the cut greatly depends on well the diamond is shaped and here the table, and specifically, the diameter of this surface is critical when it comes to the final quality of the stone.

In the diamond-cutting industry, there are certain fixed standards when it comes to the size of the diamond’s table. This is a technical subject matter that corresponds to how the diamond table is shaped in relation to the girdle and in relation to the total diameter of the stone. Diamond cutters adopt specific calumniations when determining the size of the table, which greatly depends on the type of cut of the stone and preceding its overall carat (size). Usually, the table percentage is a function of dividing the width of the diamond’s table by the overall width of the stone.

Here the diamond seeker needs to pay attention to the specific cut and shape of the diamond of choice. As diamond cuts that are other than the classical round brilliant cut: such as fancy cut diamonds (e.g. emerald cut stones) tend to have a higher table percentage than it is for the traditional round brilliant cut.