Glossary
AGS
AGS - American Gem Society - is one of the world's leading diamond grading laboratories.
ALEXANDRITE
The alexandrite birthstone is used as the birthstone to represent the month of June, and is normally a green colour in daylight. This stone is most often found in Russia and Sri Lanka.
AMETHYST
Typically found in the USA, Canada, Brazil and South Korea, the amethyst gemstone was reportedly used in Greek and Roman times to protect against drunkeness. Amethyst is the birthstone representing the month of February, and is is also used to signify 4th, 6th and 17th wedding anniversaries.
APPRAISAL
An appraisal is often carried out on items of diamond jewellery - most commonly diamond engagement rings - to provide the end customer with complete peace of mind.
AQUAMARINE
The aquamarine gemstone is typically found in Africa, Russia, Sri Lanka and Brazil. Aquamarines are used as the birthstone representing the month of March.
ASSCHER CUT
Asscher cut is the name given to diamonds which are square in shape with chamfered corners, with step cut facets. This step cut is very similar to that displayed by emerald cut diamonds.
BAGUETTE CUT DIAMONDS
Baguette cut diamonds are rectangular in shape, similar to emerald cut diamonds, but most commonly smaller, and typically used for shoulder decoration on diamond engagement rings and other diamond rings.
BLEMISHES
This term is used to when the diamond has scratches or marks on the external area of the stone.
BLOOD DIAMONDS
The phrase which is given to diamonds which are mined in conflict zones. This issue was brought into the public spotlight in late 2006 when the Hollywood blockbuster "Blood Diamond" was released, starring Leonardo DiCaprio.
BLUE TOPAZ
The name of the blue topaz gemstone is derived from the Greek word "topazios", and island in the Red Sea, and is the state gem of Utah in the USA. The blue topaz gemstone is the birthstone for the month of November and is used for the 23rd wedding anniversary.
BRILLIANCE
Liveliness or sparkle in a stone when light is reflected from the surface and from the internal reflection of light.
BROWN DIAMONDS
Brown diamonds are also known as chocolate diamonds and are increasing in popularity all the time. These brown diamonds fall into the 'fancy coloured diamonds' family of diamonds.
CARAT
Refers to the measure of weight of a diamond. For more information, please visit our diamond education page.
CARBON SPOTS
Included crystals that have a dark appearance, rather than a white or transparent appearance when viewed under a microscope. In most cases, these dark inclusions are not visible to the naked eye, and do not affect the brilliance of the diamond.
CERTIFICATION
The only way to ensure the quality of a diamond is to buy certified diamonds. This means that the diamond is accompanied by a grading certificate which follows the diamond throughout its life. This diamond grading certificate contains information about the diamond such as the diamond carat weight, diamond colour, diamond clarity, diamond measurements, diamond flouresence and the proportions of the diamond. With GIA certified diamonds, the GIA registration number of the certificate is also microscopically laser inscribed into the girdle of the diamond to ensure that both the diamond and the diamond grading certificate match up together.
CHANNEL SET
When diamonds are channel set, it means that the diamonds run between two strips of metal rather than being set in claws. This form of setting is most commonly found in diamond eternity rings.
CLARITY
A diamond often has natural imperfections, commonly referred to as "nature's fingerprints". Inclusions can be white, black, colourless or even red or green. Most inclusions are undetectable by the human eye and can only be seen with 10x magnification. Inclusions are ranked on a scale of perfection called 'clarity' ranging from IF (Internally Flawless) through to I (Included). For more information, please visit our diamond education page.
CLARITY ENHANCED
This is the phrase given to diamonds which have been treated to artificially enhance their appearance. When buying diamonds, you are generally better off buying natural, untreated diamonds, rather than clarity enhanced diamonds.
CLAW SET
The vast majority of diamond engagement rings use claw settings to display diamonds. In a solitaire diamond engagement ring, for example, a brilliant round cut diamond is held in place with 4 claws, with the bottom tip of the diamond sitting in a 'basket', or bezel. Claw settings can be 2 claw, 4 claw or 6 claw, and can normally accommodate most shapes and size of diamonds. Claw settings are generally beleived to maximise the internal light refraction inside the diamond, and therefore allow the diamond to project maximum sparkle and brilliance, thus maximising the beauty of the diamond.
CLOUDS
A grouping of a number of extremely tiny inclusions that are too small to be distinguishable from one another, even under magnification. The result is that, under a microscope, this grouping often looks like a soft transparent cloud inside the diamond. Of course, clouds cannot be seen with the naked eye. Usually, this sort of inclusion does not significantly impace a diamond's clarity grade.
CLOUDY
Diamonds of poor quality, and sometimes which have very strong flouresence, can take a on cloudy - or "milky" effect - which detracts from the value of the diamond.
COLOUR
Diamonds are graded on a colour scale established some 70 years ago by the GIA (Gemological Institute of America). The scale ranges from D (rare white) to Z (yellow). For more information, please visit our diamond education page.
COLOURED DIAMONDS
Whilst most people think of diamonds as being white in colour - and indeed the vast majority are - diamonds actually exist in many different colours - hence the name "fancy coloured diamonds" - such as green diamonds, red diamonds, orange diamonds, purple diamonds, brown diamonds, grey diamonds and black diamonds.
COLOURLESS
The phrase colourless refers to the whiteness of a diamond. Diamond colour ranges from D to Z, with D being the very whitest and Z being yellow. Typically, the closer to colour, the more valuable the diamond. This is why D-Flawless is regarded as the very best - colour D with flawless clarity. As a general rule, colours D to F are rare white, G is white, and H-J have a slight yellow tint.
COMPARISON OF DIAMONDS
The world of diamonds can often be a bit of a minefield, and there is such as thing as too much information! Therefore, how do you compare diamonds? Working in certified diamonds provides the best way of doing this as nowadays, diamond certificates tell you 95% of all you need to know about a diamond.
CONFLICT-FREE
This is the name given to diamonds which have followed legitimate supply chains from mine to retail. In the late 1990s, the funds from diamonds mined in certain central African countries such as Sierra Leone were known to have been used to fund illegal activities such as terrorism and civil wars. In the year 2000, the diamond industry introduced a self-regulation scheme known as the Kimberley Process which makes the whole diamond supply chain much more transparent through a series of warranties. Everyone associated with diamonds - merchants, retailers and customers alike - should always buy conflict-free diamonds.
CRYSTALLISED CARBON
Diamonds....in their natural form.
CUBIC ZIRCONIA
A cubic zirconia is an imitation - or synthetic - diamond. A cubic zirconia weighs less and has less sparkle than a real diamond. You will most often find cubic zirconia stones in fashion jewellery, or in replica / sample rings.
CULET
Pronounced "Queue-lay", this is the bottom point of the diamond. Occasionally, the culet of the diamond is a surface instead of a point.
CULLINAN DIAMOND
This was the laregst rough diamond ever found when it was discovered in 1908, weighing an astonishing 3,106ct. Nine diamonds were cut from this rough diamond, and the two largest of these diamonds are now part of the British Crown Jewels.
CUSHION CUT DIAMONDS
Cushion cut diamonds have four sides with curved corners. These diamonds have less avsailability than other shapes of diamonds such as round brilliant cut diamonds or princes cut diamonds for example. Cushion cut diamonds are most commonly found in diamond engagement rings, often displayed with shoulder diamonds.
CUT
This refers to the angles and proportions a skilled craftsman creates in transforming a rough diamond into a polished diamond. Based on scientific formulae, a well cut diamond will internally reflect light from one mirror-like facet to another and disperse and reflect it through the top of the stone. This results in a display of fire and brilliance. For more information, please visit our diamond education page.
DE BEERS MILLENNIUM STAR DIAMOND
Mined in the early 1990s, the De Beers Millennium Star is so flawless and so great in size that diamond experts cannot put a price on it. It weighs an amazing 203ct and is pear shaped, and is now the world's only internally and externally flawless diamond. It was subject to an attempted theft when on display at the Millennium Dome on the year 2000, but this was foiled by the British Police, and now remains in the safe hands of De Beers.
DEPTH
The height of a diamond from the culet to the table. The depth is measured in millimetres, or as a percentage of diameter. For more information, please visit our diamond education page.
DIAMANTAIRE
This is the term used to describe someone associated with the diamond industry, usually a diamond cutter.
DIAMOND
A diamond is the hardest known natural substance. It is crystallised carbon. Diamonds are mined in their rough form and then cut and polished to reveal their brilliance. Diamonds are worn by people as potent symbols - of love, devotion, pride, wealth and power. Diamonds, therefore, are the perfect gift for the perfect occasion. Diamonds are also used as the birthstone for the month of April.
DIAMOND CUTTING
The method by which a rough diamond that has been mined from the earth is shaped into a finished, faceted stone.
DIAMONDIFEROUS
This is the phrase used to describe or denote areas of land which are rich in diamonds.
DISPERSION
When light enters a diamond, it reflects off the facets and the angles cut into the stone. This distribution of light is known as dispersion, or the display of the spectral colours.
DRESDEN GREEN DIAMOND
This is the world's largest natural green diamond at 40.70ct, and is currently on display in Dresden, after having been confiscated by the Russians after World War II.
EGL
EGL - the European Gemological Laboratory - is one of the world's leading diamond grading laboratories, with offices around the world. EGL was founded in 1974.
EMERALD
Not to be confused with emerald cut diamonds, the emerald gemstone is green in colour and are most commonly located in Africa, Brazil, India and Russia. An emerald gemstone is the birthstone for the month of May and is also used on a 20th, 35th or 55th wedding anniversary.
EMERALD CUT DIAMONDS
Rectangular in shape, emerald cut diamonds are more understated than any other shapes of diamonds. This is because they are step-cut and have fewer facets, thus providing less sparkle - this, however, is deliberate, as emerald cut diamonds are not necessarily cut for sparkle, but more for the classical beauty look. Because emerald cut diamonds have fewer facets, inclusions can be more visible, therefore it is advisable to buy into a higher clarity grade. Emerald cut diamonds are most commonly found in diamond engagement rings.
ENGRAVING
This is the process by which it is possible to have a message inscribed onto a piece of jewellery. Engraving is most commonly found on wedding rings, containing usually the date of a couple's wedding. However, it is also possible to engrave other pieces of diamond jewellery such as diamond engagement rings for example.
EYE-CLEAN
A term used in the jewellery industry to describe a diamond with no blemishes or inclusions that are visible to the naked eye (ie a human eye which is not aided by magnifying devices such as a jeweller's loupe or a microscope).
FACE-UP
This phrase means looking into a diamond from the table - ie straight down into the diamond rather than looking at it from the side.
FACETS
These are the tiny surfaces polished onto a rough diamond that gives a finished diamond its shape. The way the light interacts with these facets affects a diamond's brilliance and sparkle. For more information, please visit our diamond education page.
FANCY SHAPES
Any diamond shape other than round. For example, Princess cut diamonds (square), Emerald cut diamonds (rectangular), Marquise cut diamonds, Oval cut diamonds, Pear cut diamonds or Heart cut diamonds. For more information, please visit our diamond education page.
FEATHER
A feather is a type of inclusion of flaw within the diamond.
FINISH
The word finish is used to describe the exterior of the diamond. If a diamond is well polished, it has a very good finish.
FIRE
Often a term used instead of 'dispersion'. It is the variety and intensity of rainbow colours seen when light is reflected from a diamond.
FLAWLESS
This phrase relates to the clarity of a diamond. Flawless diamonds are highly sought after - they are diamonds with zerio inclusions, or imperfections. 95% of all diamonds have flaws - this is why flawless diamonds are so rare. As a result of their scarcity, flawless diamonds command price premiums.
FLOURESENCE
When exposed to ultraviolet light, a diamond may exhibit a more white-ish, yellow-ish or blue-ish tint, which may imply that the diamond has a property called 'flouresence'. The untrained eye can rarely see the effects of fluoresence. Diamond grading reports state whether a diamond has fluoresent properties. Flouresence is not considered a grading factor, only a characteristic of that particular diamond. It is the effect of ultraviolet light on boron atoms that are found within certain diamonds. Interestingly, it is for this reason that UV light is used by diamond mining operations to aid in finding diamonds. For more information, please visit our diamond education page.
FOUR CS
This is the layman's phrase for the international diamond grading system for diamonds across the world, which was founded and initiated by the GIA in the 1930s. The "4Cs" are Cut, Carat, Colour and Clarity.
GIA
The GIA - Gemological Institute of America - is generally regarded within the diamond industry as being the world's leading diamond grading laboratory, setting standards to which all others aspire. It has the most strict standards when it comes to diamond grading and it was the GIA who founded the international diamond grading system (the 4 Cs of diamonds) which is used across the world today. The GIA have heardquarters in California, with offices across the world.
GARNET
Most usually found in Madagascar, the USA, Russia and Turkey, the garnet gemstone is the birthstone representing the month of January, and is also used to celebrate the 2nd or 6th wedding anniversary.
GIRDLE
The outer edge, or outline, of the diamond's shape. The girdle is not graded, but rather it is described by its appearance at its thinnest and thickest points. The descriptions of girdle thickness range as follows; extremely thin, thin, medium, slightly thick, thick, extremely thick. While it is less desirable for a round diamond to display an extremely thin or extremely thick girdle, such girdle widths are more common and acceptable in fancy shaped diamonds. For more information, please visit our diamond education page.
GOLDEN JUBILEE DIAMOND
One of the most famous diamonds in the world. It was found in 1986 in South Africa and weighed an amazing 755.50ct in its rough form, and is now the largest cut diamond in the world, weighing 545.67ct. It is yellow/brown in appearance and is currently on display at the Royal Museum in Bangkok.
HALLMARKING
Having been legislation in the UK for the past 3 centuries, hallmarking represents one of the earliest forms of consumer protection. Essentially, ever piece of precious metal jewellery sold in the UK has to be hallmarked. The hallmark is a tiny stamp embossed into the metal, which confirms the precious metal content of the jewellery item. This hallmarking process is carried out by one of 4 Assay Offices in the UK - London, Birmingham, Sheffield and Edinburgh. There is a different hallmark for each precious metal.
HEARTS & ARROWS CUT
The Hearts & Arrows cut is only found in rround brilliant cut diamonds and is usually a sign of an ideal cut of diamond, and so these cuts of diamonds command a price premium. The Hearts & Arrows refers to the shapes that can be seen inside the diamond when viewing from the table and from underneath.
HEART CUT DIAMONDS
Growing in popularity all the time, heart cut diamonds - compared to their round brilliant cut diamonds and princess cut diamonds counterparts - relatively difficult to find due to their unique shape. Their heart shape obviously lends itself perfectly to items which represent symbols of love such as diamond engagement rings for example.
HRD
Based in Antwerp, the HRD is the main diamond certifying body for diamonds coming through Belgium
IGI
IGI is the abbreviation for the International Gemological Institute - one of the world's leading diamond grading labotories.
INCLUSION
A clarity characteristic found within a diamond. Most inclusions were created when the gem first formed in the earth. For more information, please visit our diamond education page.
INTERNALLY FLAWLESS
The very best clarity grade of diamonds, meaning that the diamonds have zero imperfections. These diamonds are highly prized.
JEWELLER
The common name assigned to a person who works in the diamond trade, normally in a retail environment.
JONKER DIAMOND
The Jonker diamond was found in 1934 by a single diamond miner who at first thought it was a piece of glass, but it transpired it was the fourth largest gem-quality diamond ever found. In 1977, the Jonker diamond was sold to a private individual for a reported £1.25m.
KARAT
Not to be confused with carat (for the weight of diamonds), karat singifies the purity of precious metals - for example, 9kt white gold, 18kt yellow gold etc.
LENGTH TO WIDTH RATIO
If you have the physical measurments of a diamond, then you can calculate the length to width ratio. For example, with emerald cut diamonds, they ideally need to be rectangular in shape. If the emerald cut diamond is 6.50 x 4 x 2.5, then the length to width ratio is 1.63:1.00, which suggests it is nicely rectangular in shape. If the diamond is 5 x 4.5 x 3, then it suggests the diamond is more square than rectangular.
LIFETIME CARE PROGRAMME
This is a type of after-sales care programme for your diamond engagement rings and diamond jewellery. Diamonds, like anything of value, need looking after, so it is a good idea to submit your diamond engagement ring for a regular security check-up and professional repolish.
LOYALTY BONUS SCHEME
This is where existing customers are provided with an incentive to make a repeat purchase with a retail store.
MARQUISE CUT DIAMONDS
With two curved sides and two pointed ends, marquise cut diamonds are growing in popularity, and are classed under the "fancy shaped diamonds" umbrella, together with princess cut diamonds, heart cut diamonds, oval cut diamonds, emerald cut diamonds etc - ie any diamond shapes other than brilliant round diamonds. Most commonly found in marquise cut diamond engagement rings.
MEASUREMENTS
This phrase relates to the physical measurements of diamonds. This is particularly important when considering purchasing fancy shape diamonds such as princess cut diamonds, emerald cut diamonds, oval cut diamonds, heart cut diamonds or marquise cut diamonds for example. This is because the shape is all important to the overall appearance of the diamond - for instance, princess cut diamonds need to be square in shape, whilst emerald cut diamonds need to be rectangular in shape etc. The physical measurements of diamonds, therefore, provide this invaluable information.
OVAL CUT DIAMONDS
As their name would suggest, oval cut diamonds are oval in shape and provide an excellent alternative to the more 'standard' round brilliant cut diamonds. They have a similar number of facets to round diamonds, so the sparkle is similar, yet oval cut diamonds can often provide slightly better value for money. Most commonly found in oval cut diamond engagement rings.
PALLADIUM
Palladium is a noble metal and part of the platinum family. Whilst it is very similar in appearance to platinum, it is less heavy and more widely available and so provides an excellent price alternative.
PAVE
Pronounced "par-vay", this is a style of jewellery setting in which numerous small diamonds are mounted close together to create a glistening diamond crust that covers the whole piece of jewellery and obscures the metal under it.
PAVILION
Bottom portion of the stone, under the girdle, measuring to the culet. For more information, please visit our diamond education page.
PEARL
Pearls are primarily produced by molluscs such as "pearl oysters". Typically they are white in colour but, in reality, can be found in almost any colour. Pearls are used as the birthstone for the month of June and are considered to offer the power of love, money, protection and luck.
PERIDOT
The birthstone for the month of August, peridot is used for a 16th wedding anniversary, and is commonly found in many regions across the world. The largest peridot ever found - at 310ct - is currently on display at the Smithsonian Museum in Washington DC, USA.
PINK GOLD
Also known as red gold or rose gold, pink gold is, in essence, 75% gold and 25% copper, resulting in a precious metal finish with a red/pink finish. This gold is often used in the setting of diamonds into diamond engagement rings.
PINK TOURMALINE
Most commonly found in Brazil and Africa, the pink tourmaline gemstone is the birthstone for the month of October, and is given on a 8th wedding anniversary.
PLATINUM
More and more people aspire to platinum as the preferred choice for the setting of diamonds. In the UK, 950 grade platinum is the best possible. Platinum is the purest and, therefore, the most durable of all the precious metals used in diamond jewellery production. Whilst all precious metals scratch - including platinum - it does not tarnish as white gold does, for example. Platinum is often found in diamond engagement rings. Platinum is rare - if you were to metl down all the platinum that is used in diamond jewellery across the world today and pour into an olympic sized swimming pool, it would scarcely cover your ankles. This scarcity, however, means that platinum commands a price premium over all other metals in the diamond jewellery market.
POLISH
Indicates the care taken by the cutter in shaping and faceting the rough stone into a finished and polished diamond.
PRECIOUS METALS
Precious metals is the phrase commonly given to noble metals which, in themselves, have a value such as gold and platinum. Most diamond jewellery is created using 18kt white gold, 18kt yellow gold or 950 platinum. DeJoria also now offers palladium which is a recent introduction to the diamond jewellery market.
PRINCESS CUT DIAMONDS
Square in shape, princess cut diamonds are the second most popular shape of diamonds of all. They have right angled edges and have as many facets as brilliant round cut diamonds. This shape of diamond is commonly found in princess cut diamond engagement rings.
PROPORTIONS
The proportions of a diamond are very important, so that the maximum amount of light can be reflected off and out of a stone. Proportion is the relationship between the angles of the facets of the crown and pavilion. For more information, please visit our diamond education page.
RADIANT CUT DIAMONDS
Radiant cut diamonds provide the best of both worlds - the brilliance and sparkle of round brilliant cut diamonds, with the rectangular shape of emerald cut diamonds.
RING SIZE
Ascertaining the ring size of your partner can sound like a nightmare, but the reality is that it is easier than you might think. In the UK, letters are used, with 95% of women having a finger size of anywhere between J - Q (with the average being size M). In the USA, numbers are used. It is possible to have half - and even quarter - sizes.
ROSE GOLD
Sometimes also referred to as pink gold or red gold, rose gold is most commonly found in its 18kt form and is used in the creation of different diamond jewellery such as engagement rings, for example. Rose gold is basically 75% gold and 25% copper.
ROUND BRILLIANT CUT DIAMONDS
Of all the shapes of diamonds, round brilliant cut diamonds are by far the most popular, comprising around 65% of the total diamond market. Round diamonds have the most facets and therefore provide the most sparkle of all the diamond shapes. Round diamonds are most commonly found as the centrepiece of diamond engagement rings.
RUBY
The ruby gemstone is typically given to represent a 40th wedding anniversary and is normally red in colour. The ruby is the birthstone for the month of July.
SAPPHIRE
The most common colour of the sapphire gemstone is blue, but it can actually be found in almost any colour. The sapphire represents the birthstone for the month of September.
SHAPE
The physical shape of diamonds - eg round diamonds (round brilliant cut), square diamonds (princess cut), rectangular diamonds (emerald cut) etc.
SYMMETRY
A diamond's symmetry is the arrangement of the facets and finished angles, created by the diamond cutter. Excellent symmetry of a well cut and well proportioned diamond can have a great effect on the diamond's brilliance and fire. For more information, please visit our diamond education page.
TABLE FACET
This is the largest facet of a diamond. It is located on top of the stone. For more information, please visit our diamond education page.
TABLE SPREAD
Term used to describe the width of the table facet, often expressed as a percentage of the total width of the stone. For more information, please visit our diamond education page.
TAPERED BAGUETTE CUT DIAMONDS
Tapered baguette cut diamonds are most commonly found in the shoulders of diamond engagement rings, helping to highlight the beauty of the centre diamond. Called tapered as they are wider at one end than the other.
TENSION SETTING
This phrase is used to describe the setting of a diamond held in place simply by the tension of the metal surrounding it - in other words, the diamond does not sit in a bezel. Beware....tension settings can be problematic, especially when it comes to resizing. Obviously if a diamond ring is made in a particular size and then needs to be resized, this will alter the tension of the metal in the ring which could therefore jeopardise the security of the diamond in the setting.
THE REGENT DIAMOND
The history of the Regent Diamond is an amazing one. Having been discovered in India in 1701, the diamond was sold to Thomas Pitt in England to have it cut and polished from its original rough diamond weight of 410ct. The result was a cushion cut diamond weighing 140ct. It then passed through the hands of the Duke of Orleans, the crown of Louis XV, and the hat of Marie Antoinette. After the French Revolution, the diamond was set into the hilt of Napoleon Bonaparte's sword. Today, the Regent Diamond resides in the French Royal Treasury at the Louvre in Paris.
TRILLIANT CUT DIAMONDS
Trilliant cut diamonds are triangular in shape and most often used as shoulder diamonds to enhance the beauty of an alternately shaped centre diamond in diamond engagement rings.
TURQUOISE
The turquoise gemstone is the birthstone for the month of December and is an opaque blue to green mineral in appearance. It is often found in the USA, and is also a planetary stone for the Taurus, Aquarias and Saggitarius starsigns.
ULTRAVIOLET LIGHT
Ultraviolet light and rays are used under laboratory conditions to detect the degree to which diamonds have flouresence. Flouresence is where the diamond turns blue under UV light, which can be graded as none, faint, medium, strong or very strong blue. The more flouresence a diamond has, typically the less valuable it becomes. The is a small amount of UV rays in natural daylight.
WHITE GOLD
When mined from the ground, gold is, of course, yellow in colour. During the production process, this yellow gold is mixed with a series of different alloys to produce white gold which can either be 9kt or 18kt. White gold jewellery, to provide the sparkling finish, is plated with rhodium. It is this rhodium plating which can start to tarnish after wearing the item for around 12-18 months. To re-rhodium plate an item of diamond jewellery is a very quick and inexpensive process. White gold has been the preferred choice for diamond engagement rings for many years, although platinum is now the most popular, despite platinum being around 50% more expensive than its gold counterpart.
YELLOW GOLD
Yellow gold provides a warm backdrop for the setting of diamonds. It is the most traditional metal for setting diamonds, but is nowadays less popular than white gold or platinum. Ultimately, which of the precious metals you have your diamonds set into is predominantly determined by individual preference and taste.














