Blog

An Incredible Discovery of a Triangular Iron-Bearing Inclusion Within a Natural Diamond! A striking triangular feature was observed in a natural diamond, captured under the microscope in our London laboratory. Inclusions like this are far more than blemishes: they are a record of the extraordinary conditions under which the crystal grew, and they are one of the most powerful tools we have for confirming that a stone is natural. Table of ContentsAn Incredible Discovery of a Triangular Iron-Bearing Inclusion Within a Natural Diamond!What We Saw Under the MicroscopeWhy Is the Inclusion Triangular?What Causes the Orangey-Brown Colour?Why Inclusions Matter in a Natural DiamondOther Hidden Wonders Inside DiamondsHave Your Natural Diamond Examined What We Saw Under the Microscope At first glance the stone looked like any other well-cut diamond. At 40x magnification, however, a sharply defined, orangey-brown triangle appeared beneath the table facet, its three sides perfectly straight and its colour in vivid contrast to the colourless crystal around it. The image above shows exactly what our gemmologist saw through the eyepiece. Why Is the Inclusion Triangular? This triangle reflects the diamond’s natural octahedral growth structure within its cubic crystal system. A diamond octahedron is made up of eight triangular faces, and as the crystal grew layer by layer, anything trapped between those layers took on the same three-sided outline. Triangular shapes are therefore a signature of natural growth, seen in features such as trigons on rough crystal faces and in the geometry of many included crystals. Laboratory-grown diamonds grow in a very different way. HPHT (high pressure, high temperature) crystals develop cube and octahedral faces together, while CVD (chemical vapour deposition) material grows in flat layers, so their inclusions and growth patterns look distinctly different under magnification. What Causes the Orangey-Brown Colour? The orangey-brown colour is caused by a trapped iron-bearing mineral inclusion that has naturally altered over time, creating its distinctive rusty appearance instead of remaining clear. Just as iron rusts when exposed to air and moisture, iron-rich minerals trapped in a diamond can oxidise along tiny fractures that reach the surface, staining the feature a warm brown. Iron-bearing minerals are relatively common guests inside a natural diamond. Garnet, chromite, olivine and various sulphides are all found as inclusions and, because they formed at the same time as their host 150 kilometres or more below the Earth’s surface, they give geologists a rare glimpse of the deep mantle. Why Inclusions Matter in a Natural Diamond Proof of origin: included crystals and growth features confirm the stone is natural rather than laboratory grown. Clarity grading: the size, number, position and visibility of inclusions determine the clarity grade on a report, from Flawless down to Included. Identification: an inclusion is a fingerprint that is unique to one stone, which is how a diamond can be matched to its report years later. Durability: large inclusions that reach the surface or sit near the girdle can make a stone more vulnerable to chipping. The Gemological Institute of America (GIA) grades clarity on the same 11-grade scale we use at E.D.R, and an inclusion like this one would be plotted on the stone’s clarity diagram. Other Hidden Wonders Inside Diamonds This is just one of the many hidden wonders that can exist within diamonds. Clouds of microscopic pinpoints, feathers that flash like tiny mirrors, green garnets, and even smaller diamonds trapped inside larger ones have all passed across our microscope stage. Many natural stones also reveal a hidden glow under ultraviolet light, which we explore in our article on fluorescence in diamonds. If you are curious about how inclusions shape value, our guides to the 4Cs and to diamond shape and cut explain how clarity fits alongside colour, cut and carat weight, and how a laboratory-grown diamond is separated from a natural one. Have Your Natural Diamond Examined Got a question about any of your diamonds? Whether you want confirmation that a stone is natural, a full grading report, or simply to see what is hiding inside your own gem, get in touch today and we’ll be happy to assist you in finding the right solution for you!

Diamond Shape and Cut A diamond’s beauty, rarity and price all depends on the interplay of all the well-known 4 C’s: • Carat • Clarity • Colour • Shape and Cut The Shape and Cut refers to the diamonds shape and cut style – Round, Square, Pear, or Heart for example. Since a round diamond is symmetrical and capable of reflecting nearly all the light that enters, it is the most brilliant of all diamond shapes and follows specific proportional guidelines. Non-round shapes, also known as “Fancy Shapes”, will have their own guidelines to be considered well-cut. The variety of shapes and cut let you choose your preferred shape and cut that suits your character and personality, which every time you look at your diamond will wake up your personal memories and let you fall in love with it again. Look at our website for most popular Diamond Shapes and Cuts. You can have a PDF to download and print. Diamond Shape & Cut

April’s Birthstone Diamond – A Timeless Gem of Beauty and Strength For those born in April, the diamond is not just a birthstone but a symbol of enduring beauty, strength, and history. It is one of the most iconic and revered gemstones worldwide, known for its incredible brilliance, hardness, and timeless appeal. In this blog, we will delve into the fascinating history of diamonds, why they were chosen as April’s birthstone, and what makes them so special. Table of ContentsApril’s Birthstone Diamond – A Timeless Gem of Beauty and StrengthThe History of Diamonds in JewelleryWhy Is April’s Birthstone Diamond?Diamonds in Colour – A Spectrum of BeautyThe Enduring Legacy of DiamondsApril’s Birthstone Diamonds – A Birthstone That Lasts Forever The History of Diamonds in Jewellery Diamonds have captured the human imagination for over 3,000 years, with their first recorded use in jewellery originating in ancient India. It is believed that diamonds were first regarded as sacred objects, with the ancient Greeks and Romans viewing them as divine, either as tears of gods or fragments of stars. Such beliefs about diamonds as celestial or godly entities added to their mystique and allure. Diamonds were once extremely rare and thus reserved for the wealthy and powerful. Royal families, kings, and queens frequently adorned themselves with diamonds to signify their wealth and strength. This continued reverence for diamonds persisted throughout the centuries, and the gemstones became symbols of power and authority, a status that continues to this day. During the Middle Ages, diamonds were not only worn as symbols of status but were also believed to have protective powers. Knights and warriors often wore diamonds for their supposed ability to bring invincibility and safeguard them in battle. This belief in diamonds’ ability to ward off danger and bring strength is likely why diamonds became linked to April as its birthstone. Their lasting durability and remarkable properties perfectly embody the traits of resilience and everlasting beauty, making them an ideal gem for those born in the month of renewal. Why Is April’s Birthstone Diamond? Diamonds carry deep symbolic meaning and have long been considered one of the most precious gemstones in the world. It’s no surprise that the birthstone diamond was chosen for April, a month that symbolizes renewal and strength. The tradition of birthstones can be traced back to biblical times, with references in the Book of Exodus. In the Bible, the high priest’s breastplate was said to hold twelve stones, each corresponding to a different month of the year. Over time, these stones became associated with the characteristics of the people born in each respective month, and diamonds were chosen for April because of their beauty, rarity, and symbolism of strength and resilience. The diamond’s symbolism of invincibility and power is part of its long history, and ancient cultures believed that wearing a diamond would provide protection, vitality, and courage. As one of the rarest and most valuable gemstones, diamonds also reflect the uniqueness of those born in April, making them a fitting representation of both rarity and strength. Diamonds in Colour – A Spectrum of Beauty While diamonds are most often associated with clear or colourless stones, they can come in a wide variety of colours. Diamonds come in hues ranging from yellow and blue to rare shades of green, pink, and even red. These coloured diamonds, known as “fancy coloured diamonds,” are highly prized and unique, and they form through various natural processes during their formation. For example, blue diamonds get their colour from the presence of boron, while yellow diamonds develop their hue through nitrogen. The rarest of all diamonds, green diamonds, owe their colour to natural radiation exposure. These coloured diamonds are highly sought after by collectors and jewellery lovers for their rarity and beauty. The Enduring Legacy of Diamonds Diamonds are often associated with love and commitment, especially when used in engagement rings. The phrase “A diamond is forever” has become synonymous with eternal love, further solidifying the diamond’s role as a symbol of enduring devotion. Beyond their emotional and symbolic significance, diamonds are also valued for their physical properties. As the hardest natural substance on Earth (with a Mohs hardness score of 10), diamonds are extremely resistant to scratching, although they can still chip if struck on a cleavage plane. Many natural stones also reveal a hidden glow under UV light, as we explain in our article on fluorescence in diamonds. This makes them perfect for jewellery that is meant to last a lifetime. A diamond’s remarkable hardness also allows it to reflect light in ways that create its signature brilliance and “fire,” making it the ultimate symbol of light and enduring beauty. April’s Birthstone Diamonds – A Birthstone That Lasts Forever Whether you are celebrating a birthday in April or simply have an affinity for the brilliance of diamonds, this remarkable gemstone is much more than just a gem, it is a symbol of strength, endurance, and timeless elegance. With a rich history, enduring properties, and unparalleled beauty, diamonds continue to captivate the world, making the birthstone diamond the perfect gem for those born in April. If you’re interested in learning more about your April birthstone diamond, how it is graded against the 4Cs, or how a natural stone is separated from a laboratory-grown diamond, then feel free to get in touch with our expert team today!

Diamonds aren’t just the colour you see under natural light – they reveal a hidden world of colour under ultraviolet (UV) light! When exposed to UV light, many natural diamonds exhibit fascinating fluorescence, which can range from vibrant yellows to striking blues and even bold oranges, as seen in this image. Did you know that around 25–35% of diamonds glow to some degree? Table of ContentsWhat Is Fluorescence in Diamonds?The Colours of Diamond FluorescenceHow the UV Glow Is GradedDoes Fluorescence Affect a Diamond’s Value?A Useful Identification Tool What Is Fluorescence in Diamonds? Fluorescence is the visible glow a diamond gives off when it is exposed to invisible ultraviolet light, such as the long-wave UV found in daylight or the lamps used in nightclubs and at airport security. The glow stops the moment the UV source is removed, which is what separates it from phosphorescence, where a stone continues to glow for a short time afterwards. The effect is caused by tiny structural features and trace elements that were locked into the crystal as it grew deep within the Earth. These absorb the high-energy UV light and release it again as lower-energy visible light, producing the colours we see. The Colours of Diamond Fluorescence Blue is by far the most common colour, accounting for well over 90% of fluorescent diamonds. It is linked to nitrogen-related defects within the crystal lattice and can make a slightly tinted diamond appear whiter and more brilliant under certain lighting conditions. Yellow is often seen in diamonds with a particular arrangement of nitrogen atoms, giving them a warm, inviting glow. Interestingly, diamonds that glow orange are rarer, creating a unique warmth that adds an unexpected twist to their sparkling allure. Green, white and even red are also seen occasionally, and the colour and strength of the glow are a useful fingerprint for each individual stone. How the UV Glow Is Graded Laboratories assess the reaction under a standard long-wave UV lamp and compare it to a set of master stones. Diamonds can display either none, faint, medium, strong or very strong fluorescence, and we record this on every one of our loose diamond reports at E.D.R, alongside the 4Cs of carat, colour, clarity and cut. The grade describes the strength of the glow, while the colour is noted separately. Because it is a permanent, natural characteristic of the stone, it is also a helpful check when verifying that a diamond matches its report. Does Fluorescence Affect a Diamond’s Value? In most cases, the effect on appearance is negligible and can only be seen under UV light. In fact, for diamonds in the lower colour grades (I to M), a medium or strong blue glow can be a bonus, making the stone face up whiter in daylight. Research published by the Gemological Institute of America (GIA) found that most observers could not tell fluorescent and non-fluorescent diamonds apart in normal lighting. The exception is a very small number of very strong stones that can appear hazy, milky or oily. These are uncommon, but it is the reason strongly fluorescent diamonds in the top colour grades (D to F) sometimes trade at a slight discount. Conversely, this can represent excellent value for a buyer who has examined the stone and is happy with how it looks. A Useful Identification Tool Beyond its visual appeal, the UV response of a diamond gives gemmologists valuable clues about its chemical composition and formation history. Here are a few ways we use it in the laboratory: Matching stones: diamonds in a pair of earrings or a multi-stone ring should ideally have a similar UV reaction so that they look consistent in all lighting. Spotting simulants: cubic zirconia, moissanite and glass react very differently under UV light compared with natural diamond. Screening for laboratory-grown diamonds: many laboratory-grown diamonds show distinctive patterns, colours or phosphorescence that natural stones rarely display. Confirming identity: a stone’s UV reaction is permanent, so it helps confirm that a diamond matches an existing report. For a deeper look at how colour and body tint are assessed, see our guides to coloured diamonds and April’s birthstone, the diamond. So, the next time you’re admiring a diamond, remember that its true magic may just reveal itself when you shine a UV light on it! If you would like your diamond graded, including its fluorescence, contact our London laboratory today.

What Are Coloured Diamonds? Coloured diamonds (also known as fancy coloured diamonds) are diamonds that have a noticeable colour when you view them in the face-up position. The most common colours for natural diamonds are yellow and brown. While they do exist, it’s incredibly rare to find violet, red, green, orange, blue and pink diamonds in nature. This is why they’re so valuable: out of every 10,000 diamonds, only one will have one of the stunning rare colours. Table of ContentsWhat Are Coloured Diamonds?How Coloured Diamonds Get Their ColourHow Fancy Colour Is GradedNatural, Treated or Laboratory Grown?Famous Coloured DiamondsBuying Coloured Diamonds With Confidence How Coloured Diamonds Get Their Colour A pure diamond is colourless carbon. Colour appears when the crystal lattice contains trace elements, structural defects or has been exposed to natural radiation during its billion-year journey to the surface: Yellow: nitrogen atoms grouped within the crystal absorb blue light, leaving a yellow tint. Intense yellows are often called “canary” diamonds. Blue: traces of boron, which also make these stones electrically conductive. Blue diamonds are among the rarest of all. Pink, red and purple: not caused by an impurity but by “plastic deformation” – distortion of the lattice under enormous pressure. Red is the rarest colour of all, with only a few dozen known stones. Green: natural radiation from surrounding rocks over millions of years, usually affecting just the surface skin of the crystal. Brown and orange: a combination of lattice defects and nitrogen; brown is the most common colour and is marketed as “champagne” or “cognac”. Black and grey: dense clouds of dark inclusions, often graphite, scattered throughout the stone. How Fancy Colour Is Graded A coloured diamond’s appearance is determined by how intense the colour is. The intensity is graded from “Faint” and “Very Light” through “Light”, “Fancy Light”, “Fancy”, “Fancy Intense” and “Fancy Vivid”, with “Fancy Deep” and “Fancy Dark” used for strongly saturated but darker stones. The closer to the vivid end of the scale, the brighter and more intense the colour is – and the higher the price per carat. This is the reverse of the familiar D-to-Z scale used for colourless diamonds, where less colour is better. Once a yellow or brown stone shows more colour than a Z grade, it crosses into fancy territory and its value begins to climb again. Our diamond intensity page shows the scale in more detail, and the Gemological Institute of America (GIA) developed the system used by laboratories worldwide. Alongside intensity, the grader records the hue (the dominant colour plus any modifier, such as “purplish pink”) and the tone (how light or dark the stone is). Cut is judged on how well it concentrates colour rather than on maximum brilliance, which is why fancy colours are so often cut as radiants and cushions. Natural, Treated or Laboratory Grown? Because natural fancy colours are so rare, the market contains a great many stones whose colour has been created or enhanced. Irradiation followed by heating can turn an ordinary yellowish diamond green, blue or vivid yellow; HPHT (high pressure, high temperature) processing can transform brown stones into colourless, pink or blue; and coatings can add a thin film of colour that wears away. Laboratory-grown diamonds are also produced in blue, pink and yellow. None of these is wrong to buy, provided it is disclosed and priced accordingly – a treated or laboratory-grown stone is typically worth a small fraction of a natural one. Spectroscopy, UV fluorescence and microscopic examination allow our laboratory to separate natural colour from its alternatives. Famous Coloured Diamonds The Hope Diamond: a 45.52 ct Fancy Dark greyish-blue stone now in the Smithsonian Institution. The Pink Star: a 59.60 ct Fancy Vivid pink that sold for over US$71 million in 2017, a world record for any gem. The Dresden Green: a 41 ct natural green diamond of exceptional purity, documented since 1722. The Tiffany Yellow: a 128.54 ct cushion that has been worn by only a handful of people, including Audrey Hepburn. Buying Coloured Diamonds With Confidence Whether you are drawn to an affordable champagne brown or a once-in-a-lifetime vivid pink, insist on a laboratory report that states the colour origin as natural and gives the full intensity, hue and tone grades. Read more about April’s birthstone, the diamond, and the 4Cs that underpin every grading report. If you have any questions about these diamonds, or would like a stone tested and graded, then our expert team will be more than happy to help, so get in touch today!