A-Z Glossary of Diamond Terms

Become your very own diamond expert. We help you to get to grips with the most commonly used diamond jargon in our handy glossary of terms.

• Brilliance: Brilliance is what makes a diamond sparkle. It is a measure of the proportion of light which enters a diamond and is reflected back to the eye through the top of the stone. A diamond cut to optimum proportions results in the most light being reflected back and therefore has the most brilliance.
• Carat: Carat refers to the weight of the diamond and not its size. One carat is equivalent to a fifth of a gram. The word carat originates from the Greek and Arabic names for the carob tree whose dried seeds were once used as counterweights for weighing gold and gemstones.
• Clarity: Clarity refers to the presence of the tiny natural imperfections that occur in most diamonds, known as inclusions or flaws. It's these imperfections, affectionately called "nature's fingerprints" that make every diamond unique. Generally, the fewer and smaller the inclusions, the greater the clarity and the more valuable, rare and beautiful the diamond.
• Cluster: As the name suggests, a cluster refers to multiple diamonds set closely together to form a centrepiece for jewellery. The cluster might consist of one larger central diamond framed by smaller stones or of a collection of diamonds of similar size. A cluster creates the illusion of one large stone but is less expensive than a diamond solitaire of an equivalent carat weight.
• Colour: A little confusingly, colour refers to the degree to which a diamond is colourless. The close a diamond is to having no colour, the more valuable and rare it is.
• Crown: The crown is the top portion of the diamond, extending below the table.
• Cut: Cut refers to the proportion, symmetry and finish created when a rough diamond is transformed into a polished gem. The only one of the 4 Cs that isn't created by nature, a diamond's cut relies on the exacting skills of a master cutter to unleash the stone's beauty. The better the cut, the more valuable and beautiful the diamond is. Some people do refer to "cut" as meaning the diamond's shape; however, this isn't the truest meaning of cut. 
• Diamond Shape: Diamond shape refers to the shape of the diamond as you view it from above. The most common and traditional diamond shape is round brilliant but there are a host of other diamond shapes available. Any diamond shape that isn't round brilliant is known as a "fancy diamond shape". 
• Dispersion: When white light enters the top of the diamond, it is refracted, breaking the light into its spectral colours which reach the eye in intense flashes of colour. This is known as dispersion and is also synonymous with "fire". 
• Emerald Cut: Originally designed for the cutting of emeralds, emerald cut is a popular "fancy diamond shape" with a rectangular cut and stepped corners. While it offers less brilliance than other diamond shapes, it is an elegant shape that enhances the stone's lustre and highlights its clarity.
• Facets: Facets are the flat, polished surfaces of a diamond.
• Fancy Diamond Shape: Any diamond shape that isn't round brilliant is known as a fancy diamond shape. The most popular fancy diamond shapes include princess cut, emerald cut, pear, baguette, oval, heart and marquise.
• Fancy Colour Diamond: Any diamond that isn't considered white is called a fancy colour diamond or a "fancy". Fancy colour diamonds are rare and therefore more valuable than white diamonds. Fancy colours include red, blue, pink, green and brown. 
• Fire: When white light enters the top of a diamond, it is refracted, breaking the light into a rainbow of colours which reaches the eye in intense flashes of colour. This effect is known as fire or dispersion.
• Flaws: Also known as inclusions, flaws are the tiny natural imperfections found within a diamond, such as fractures, air pockets or crystals of a foreign material. It's the presence of these flaws that affect a diamond's clarity.
• Halo Setting: A halo is a setting that encircles a central diamond (or cluster of diamonds) in a collection of smaller stones. It creates a beautiful, sparkling centrepiece that has become increasingly popular for diamond rings, pendants and earrings.
• Ideal Cut: Ideal cut is the optimum cut for diamonds, a perfectly proportioned cut that results in most of the light that enters the diamond being reflected, producing the optimum combination of brilliance, scintillation and fire. 
• Inclusions: Inclusions are tiny internal imperfections found within most diamonds, such as fractures, air pockets or crystals of a foreign material. Affectionately known as nature's fingerprints, it is inclusions that make a diamond unique. The presence of inclusions affects a diamond's clarity.
• Kimberley Process: The Kimberley Process is a joint initiative between governments, industry and society, aiming to restrict the flow of conflict diamonds used to finance wars against legitimate governments. Fraser Hart subscribes to the Kimberley Process and we insist that all our diamond suppliers do so too.
• Loupe: A loupe is a monocular handheld magnifier used by jewellers to inspect the quality of a diamond. A standard loupe will have a 10x magnification.
• Pavé Setting: In pavé settings, small diamonds are set closely together using small beads of precious metal to create an unbroken expanse of light and sparkle and a true diamond-encrusted look.
• Princess Cut: The most popular of fancy diamond shapes, a princess cut diamond is a modified version of the round brilliant diamond with squared off corners and an overall pyramid shape. It is the most brilliant of all the square and rectangular diamond shapes.
• Round Brilliant: The most popular and traditional shape for diamonds, a round brilliant diamond is cut to a round at the top and a cone at the bottom. It has 57 facets arranged with mathematical precision and, of all diamond shapes, it returns the maximum amount of light and brilliance.
• Scintillation: Scintillation is the plpay of light you see with the movement of a diamond, demonstrated by the sparkle that dances on the stone's surface. 
• Solitaire: A solitaire refers to a single diamond in a piece of jewellery or a ring. A diamond solitaire ring is the traditional choice for a diamond engagement ring.
• Table: The largest facet of a diamond, the table is the flat surface at the top of the stone.
• The 4 Cs: The 4 Cs - cut, colour, clarity and carat - are the characteristics that determine the quality, value, rarity and beauty of a diamond.