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A cut refers to the arrangement of facets on a gemstone.

The cut of a gemstone is extremely important, and is a key factor in determining its value. For example, a beautiful colour, eye clean clarity and a large carat weight will mean nothing if the stone is poorly cut.

The first step when cutting is to decide if the gem is principally going to sparkle or shine. Opaque gems are often cabochon cut to maximise the surface lustre (shine) and transparent gems are faceted to maximise the refraction of light from within the gem (sparkle). The reason transparent and sometimes translucent gemstones are therefore faceted is to let them effectively inhale light from the facets above the girdle, then to encourage the light to bounce off the facets below the girdle and then to exhale sparkles, and in some cases turn the incoming white light into a rainbow of colours.

The responsibility for transforming a rough gem excavated from a mine or an alluvial deposit to a valuable sparkling or shining gem lies entirely on the skills and expertise of the lapidarist.
There is a lot of confusion surrounding the meaning of cuts and many people often refer to shapes as cuts, so much so that the industry itself, in an attempt to simplify matters, or in some cases naivety, often refers to certain shapes as a cut. The cut of a gem really should be used to describe either the arrangement and shape of the facets, or the quality of the workmanship. It should not refer to the outline shape of the gem.

There are also certain cuts that are named after the person or the company who initially designed them. The Asscher cut, the Leo cut and the Flanders Brilliant Cut are all examples of famous cuts that were primarily designed as alternative ways for shaping Diamonds.

I have featured a selection of specialist cuts below and others will be featured throughout the book.

Briolette cut


The briolette cut is used for gemstones that are hung rather than set and therefore normally do not have a table facet. The cut is sometimes referred to as a drop cut and the facets are normally triangular.

There is no crown or pavilion with this cut and it is primarily designed to allow the stone’s facets to show a high amount of lustre.

Briolette cut gems are often partially drilled and then glue is used to secure a metal pin within the gem. This type of hanging setting is often seen in earrings and necklaces. Some beaded bracelets and necklaces also utilise the briolette cut, but in these instances a hole is drilled through the gem which is then strung on a wire.

Buff top cut


This is a cut that combines two classic styles. The top is domed with a cabochon cut, while below the girdle the gem has facets on its pavilion. The cabochon cut on the top allows for a smooth surface that allows a high amount of lustre and brilliance to show through from the facets below; it also gives the illusion of depth as the eye is drawn into the centre. This cut is very popular in gents’ jewellery.

Some in the gem trade use the term buff cut to describe cabochon cut gems that are shallow in depth.

Compass card cut


Designed by Merrill O. Murphy, a lapidarist and gem collector from New Mexico, the compass card cut is normally applied to round shaped gemstones and when viewed from the table facet (as its name suggests) you see a traditional style compass card. For those into sailing or for those looking for direction in life, this cut is a must have.
Although as this edition goes to print we are still unable to bring this cut to you, my team of lapidarists are working hard at trying to perfect it and we are hoping to be able to bring it to you in the near future.

Eight cut


Also known as the “Single Cut”, an eight cut is a variation of the brilliant cut and is often used on Diamonds under .05ct. Despite its name, it actually has 17 or 18 facets (depending on if a culet facet has been added).

On the crown, there are 8 facets plus the table, and below the girdle there are a further 8 facets on the pavilion. As with a round brilliant cut, the pavilion is slightly deeper than the crown.

The eight cut, or single cut, is applied to very small gems where it is impossible to apply more facets. Furthermore, when gems are set on solid backgrounds (such as watch faces or certain cufflink designs), if no light is able to enter from the back, then the eight cut is normally applied.

For small accent diamonds where their diameter is less than 1.4mm the 8 cut is often applied.

It’s important to fully appreciate that even these small gemstones are faceted by hand. It’s quite frustrating sometimes when people compare crystal jewellery to genuine gemstone jewellery: not only are the gems inherently more valuable, they are cut and faceted by artists and not computers.

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