Why is Cut Quality So Important (When Buying a Diamond)?

The cut of a diamond is one of the four Cs – the most important aspects of the stone. This is because diamonds are essentially completely colorless crystals, and the amazing sparkle that they can produce is almost entirely decided by the cut that is chosen for the stones.

Round Brilliant Cut

The most common cut for a diamond is the round brilliant cut, in which the diamond is shaped into a typical diamond shape when seen side-on. From the top, it seems to be a slightly flattened sphere, with the flat side up, and from the bottom, it presents as a point. This design is widely used wherever diamonds are cut because the many facets reflect the light into and out of the diamond, causing the light to bounce around inside the stone, creating an icy fire of color that is simply gorgeous to see. Many people wear diamonds at night, and this is a tremendous shame as diamonds look their best being allowed to show off in the sunlight, throwing out rainbow darts of color with every movement.

In Disguise

However, sometimes diamonds can benefit from a slightly different cut. This is if the stones contain inclusions (internal imperfections) that can affect the way the light reflects and refracts. Occlusions (external imperfections) can be delicately sliced away completely, resulting in a smaller, but counterintuitively, more valuable stone. Removing flaws and imperfections is a skill that every good cutter must learn early on in their career, as well as how to work delicately near fracture sites. There must be little more sickening for a cutter than the sight of two small and unbalanced diamonds where they were so recently working on one slightly flawed one… Despite diamond’s tremendous hardness, which helps it to cut glass, it is quite brittle and can shatter if treated poorly.

What Does Cut Actually Mean?

The word ‘cut’ can refer to both the act of physically shaping the stone to show it off in its best light and to the shape itself: round brilliant cut, as described above, the princess cut is designed to allow for sparkle while shaping the diamond into a sort of stepped rectangle. The emerald cut is usually a very geometrical rectangle with or without beveling at the edges. There are a number of shapes into which stones are commonly cut, so do acquaint yourself with all of these before you make your choice: you may find, for example, that a cushion cut diamond is the one for you, rather than the more traditional round brilliant or princess cuts.

Both types of ‘cut’ can be used to disguise any flaws inside or outside a stone, so do be aware that any stones boasting a very unusual cut will usually have a story of this type behind it. It does not necessarily detract from the stone itself or its value, so if you are taken with such a stone, do not be hesitant to invest in it.