The anatomy of a diamond

One of the most important characteristics of a diamond is the cut. The cut of a diamond determines the fire, brilliance and scintillation of the gemstone. If, a diamond is cut incorrectly it will result in a dull and muted appearance. When cut to perfect proportion and symmetry, a diamond will radiate a brilliance second to none. For a more in-depth understanding of the anatomy of a diamond view the infographic below:

The Anatomy of a Diamond Cape Town Diamond Museum


Every component of a diamond is considered to be extremely important. A table, for example, helps a diamond reach its full potential by refracting the light rays that enter the diamond. In order to divert the light that enters the diamond a table is located on the top surface of a diamond. It’s also one of the largest facets on a diamond.


The part between the girdle and the table of a diamond is known as the crown. The main function of a crown is to act as a window and to distribute light across the diamond. By doing this, the crown, which is the extension of the table, will help contribute to the fire, brilliance and scintillation of a diamond.


When it comes to the girdle of a diamond it can be either rough, faceted or polished; this will all depend on the personal preferences of the diamond cutter when the stone is cut and polished. The girdle is the thin perimeter of a diamond and consists of the outer edges of a diamond. The function of the girdle is to divide the crown and the pavilion of a diamond while making direct contact with the setting. Did you know you can inscribe a special message on the girdle of a diamond?


The pavilion consists of the bottom part of a diamond; this part connects the culet and the girdle. The function of the pavilion is to reflect light and maximising the fire, brilliance and scintillation of a diamond. But in order for this to be possible the pavilion of a diamond needs to be cut to perfection by a skilful craftsman.


The culet makes up the smallest part of a diamond at the bottom of a pavilion. It’s either a sharp point or facet, which sits parallel to the table. The function of a culet is to protect the pavilion and reduce the risk of damage on a loose diamond.


REFLECTION: Light will enter the table of the diamond and reflect back to the observer and the wearer when cut and polished to perfect proportion and symmetry.

REFRACTION: Light will travel through the centre of the diamond and bounce off from the internal walls.

DISPERSION: Dispersion causes white light, which leaves the top part of the diamond, to be separated into different colours.


SHALLOW CUT: Even though a shallow cut diamond might seem larger in size, it causes light to escape from the sides rather from the top. This will lead to the diamond having less fire, brilliance and scintillation.

IDEAL CUT: A diamond with the correct proportions and symmetry is considered to be the ideal cut. The well-proportioned cut insures light from reflecting perfectly. Learn more about the ideal proportions for a round brilliant diamond cut.

DEEP CUT: The deeper the diamond cut, the less bright the appearance is of the gemstone. This is due to the diamond being unable to reflect the right amount of light back through the table.

When referring to the brilliance of a diamond, it is interesting to note that the common notion that a diamond with more facets will sparkle more is simply not true. Find out why here.

Experience the fascinating world of diamonds like you’ve never seen it before. Visit the Cape Town Diamond Museum and witness an in-depth view of a diamond’s anatomy as well as the history. Book your free guided tour today!