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An Amazing Discovery In Baltic Amber! Like something straight out of Jurassic Park! This incredible amber piece contains not one, BUT TWO insect inclusions! Most likely, these are two crane flies often mistaken for mosquitoes. Millions of years ago, these insects became trapped in sticky tree resin. Over time, the resin fossilised and hardened into what we now know as amber. This particular piece is Baltic amber, estimated to be around 40–50 million years old and found around the Baltic region, including Russia, Poland, Lithuania, and Latvia. Other famous amber deposits include Mexico, the Dominican Republic, Myanmar, and the Isle of Wight here in the UK. Some of the oldest known amber deposits date back over 300 million years! Nature’s time capsules never fail to amaze! If you have any questions about Baltic amber or maybe have a query about a diamond or gemstone, then feel free to get in touch today and our expert team will be happy to help you.

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!

Coating Treatment For An Emerald A drilled bead was sold as an emerald… but the reality was very different. Under magnification, the colour told the story. We observed green surface coating beginning to flake, particularly around the drill hole and edges areas where wear occurs first. Testing confirmed the material beneath: white topaz, not emerald. Surface coatings like this can appear convincing at first glance, especially in beads. But they are only superficial and can degrade over time, revealing the true stone underneath. 🔍 What to look for:
 Colour concentrations around drill holes Uneven or patchy colour Signs of surface wear or flaking At E.D.R – European Diamond & Gemstone Reports, we specialise in accurate gemstone identification and coating treatment detection. If something doesn’t look quite right, especially with emeralds, have it tested.

Tourmaline, The October Birthstone The October Birthstone, Tourmaline, is celebrated for its dazzling colour range and vibrant energy. From rich greens and ocean blues to fiery reds and jet black, its variety makes it a truly unique gem for autumn birthdays. Tourmaline comes from a Sinhalese word meaning “stone with mixed colours,” perfect for a gem often found in vivid multicoloured formations. While pink tourmaline is most widely marketed for October, all colours of tourmaline are equally recognised for the month. Tourmaline is admired for its complex crystal structure and optical trait, pleochroism, where it appears different colours from different angles. Watermelon tourmaline, with its pink centre and green rind, forms naturally in concentric zones. This rare bi-coloured type is a collector’s favourite and often kept in slice form to show off its beauty. Fun fact: Tourmaline can become electrically charged when heated or rubbed, a property known as pyroelectricity and triboelectricity, making it one of the few gems with this natural ability. Symbolising protection, creativity, and emotional clarity, tourmaline is more than a birthstone, it’s a colourful force of nature. Get in touch with our team today to get additional information on your birthstone!

Opal, the October Birthstone The October birthstone, opal, is known for its phenomenal play of colour, making it a true gem of October. This mineraloid showcases a breath-taking spectrum of colours that can change with different light and angles, making each stone uniquely beautiful. Table of ContentsOpal, the October BirthstoneHow the Gem Forms and Why It Flashes With ColourThe Main Types of OpalHistory and SymbolismTreatments, Synthetics and Imitations to Watch ForCaring for Your Jewellery How the Gem Forms and Why It Flashes With Colour The gem forms when silica-rich water seeps into cracks and voids in the Earth’s crust. Over millions of years, this water gradually deposits microscopic spheres of silica. When these spheres are uniformly sized and neatly stacked, they diffract light like a natural grating, creating the captivating optical effects that fascinate gemstone lovers. The size of the spheres determines which colours appear: smaller spheres produce blues and violets, while larger spheres are needed for the rarer oranges and reds. Because it contains between 3% and 10% water and has no crystal structure, the stone is classed as a mineraloid rather than a mineral. The Main Types of Opal Precious opal: any variety that shows play of colour, whatever its body tone. Black opal: a dark grey to black body tone that makes the colours blaze. The finest material comes from Lightning Ridge in New South Wales, Australia, and it is the most valuable of all. White or light: milky white to pale body tones, mined mainly at Coober Pedy and Mintabie in South Australia. Boulder: thin veins of precious material still attached to their ironstone host rock, from Queensland. Crystal: transparent to semi-transparent material with play of colour visible right through the stone. Fire opal: a transparent yellow, orange or red stone from Mexico, prized for its body colour and sometimes showing no play of colour at all. Common (potch): material with no play of colour, including the pink, blue and green varieties from Peru. Australia supplies around 90% of the world’s precious material, with Ethiopia’s Wollo province emerging since 2008 as an important source of bright, hydrophane stones that can temporarily absorb water. History and Symbolism Historically, opals have symbolised hope, purity and truth, with many cultures considering them to be lucky charms. The name originates from the Sanskrit word “upala,” meaning “precious stone.” Ancient Romans believed the gem held protective powers, while medieval Europe regarded it as a symbol of royalty. Queen Victoria was a devoted admirer and did much to restore its popularity after a superstition, sparked by a 19th-century novel, linked it with bad luck. Fun fact: did you know that it is sometimes referred to as the “stone of hope”? They are also believed to enhance creativity and inspire originality in those who wear them. The gem shares October with tourmaline, which was added as a second birthstone in 1912. Treatments, Synthetics and Imitations to Watch For Because fine black material is so valuable, the market contains plenty of look-alikes. Doublets and triplets glue a thin slice of precious material onto a dark backing (and, for triplets, under a clear quartz dome) to imitate a solid black opal. Porous Andamooka matrix material is often sugar-and-acid treated to darken its body tone, and synthetic material has been manufactured since the 1970s, usually recognisable by its unnaturally regular “lizard skin” or columnar colour patches. A gemmological examination quickly separates these from natural solid stones, and the Gemological Institute of America (GIA) provides a useful overview of the gem’s properties and treatments. Caring for Your Jewellery With a hardness of only 5.5 to 6.5, it scratches more easily than most gems, so choose protective settings for rings and avoid wearing them for manual work. Never use ultrasonic or steam cleaners; wipe gently with a soft, damp cloth. Avoid sudden temperature changes and very dry conditions, which can cause crazing (fine surface cracks) in some material. Doublets and triplets should never be soaked in water, as the glue layers can fail. With their enchanting beauty and rich history, this is not just a birthstone; they are a treasured gem for those who appreciate nature’s artistry. Explore the full year on our birthstones page, or get in touch today to have your own October birthstone identified and reported on by our London laboratory.

Natural vs Cultured Pearls: What’s the Difference? While both natural and cultured pearls may appear visually similar, displaying a lustrous surface and rounded form, their internal structures and origins are fundamentally different. Understanding that difference is essential, because it can mean a hundred-fold difference in value between two strands that look almost identical. Table of ContentsNatural vs Cultured Pearls: What’s the Difference?How Natural Pearls FormHow Cultured Pearls Are GrownWhy Natural Pearls Are So Rare and ValuableHow a Laboratory Tells Them ApartBuying, Selling or Valuing Pearls? How Natural Pearls Form Natural pearls form organically in the wild when an irritant, such as a parasite, enters a mollusc, prompting it to secrete concentric layers of nacre over many years. Unlike cultured pearls, natural pearls are composed entirely of nacre, with no artificial core or nucleus. This slow, organic process results in pearls that are not only rare but also uniquely beautiful in structure. The image below shows a cross-section of a natural pearl, where you can clearly see the delicate growth rings, each representing a layer of nacre built up over time, much like the rings of a tree. How Cultured Pearls Are Grown In contrast, cultured pearls are the result of controlled pearl farming, where a technician surgically inserts a nucleus (usually a spherical bead made from freshwater mussel shell) along with a piece of mantle tissue into the mollusc. This stimulates nacre production under farmed conditions. The technique was perfected in Japan by Kokichi Mikimoto and others in the early 1900s and transformed pearls from a royal luxury into an accessible gem. Cultured pearls can develop in as little as six months to a few years, depending on the variety: Akoya: the classic white, round pearl from Japan and China, usually 6–9 mm with a sharp, mirror-like lustre. South Sea: the largest and most valuable, in white, silver and gold, grown in Australia, Indonesia and the Philippines. Tahitian: naturally dark pearls in peacock green, aubergine and silver, from French Polynesia. Freshwater: usually tissue-nucleated with no bead, grown in Chinese lakes and rivers in a wide range of shapes and pastel colours. Why Natural Pearls Are So Rare and Valuable Due to overharvesting in the late 19th and early 20th centuries, particularly in regions of the Persian Gulf, India and Sri Lanka, natural pearls became scarce. As a result, they are now rarely seen on the market and command significantly higher prices due to their rarity and historical importance. Many of the finest examples appear only at auction, often in antique jewellery that predates the cultured era. Because the two can look identical to the eye, antique strands and brooches are the pieces most frequently found to contain cultured pearls that have been mistakenly described as natural – and, occasionally, the reverse. How a Laboratory Tells Them Apart At E.D.R – European Diamond & Gemstone Reports, we offer advanced X-ray analysis and full gemmological testing to accurately identify natural versus cultured pearls. Our lab can detect internal growth structures, confirm the presence or absence of a nucleus, and provide professional certification for both loose pearls and mounted jewellery. X-radiography: reveals the concentric structure of a natural pearl or the bead nucleus and thin nacre coating of a bead-cultured pearl. Microscopy: drill holes and surface features often show the boundary between nacre and nucleus. Ultraviolet fluorescence: helps separate natural colour from dyed or irradiated pearls. Testing for imitations: glass and plastic imitation pearls feel smooth when rubbed gently against a tooth, whereas real nacre feels slightly gritty. These are the same methods used by major laboratories worldwide, including the Gemological Institute of America (GIA). To learn more about the gem itself, read our guide to June’s birthstone, the pearl. Buying, Selling or Valuing Pearls? Whether you’re buying, selling or valuing pearls, trust E.D.R for precise, expert-level pearl identification and reporting. We issue a Jewellery Card Report for mounted pieces and a Loose Gemstones Report for individual pearls and strands, and we can also provide an insurance valuation. Get in contact today for pricing and any other pearl enquiries or questions you may have.

The Beautiful Sapphire, The Birthstone Of September September’s birthstone, the sapphire, is celebrated for its stunning hues and remarkable durability. As a member of the corundum family, these gems rank 9 on the Mohs scale, making them exceptionally hard and ideal for everyday wear. While most people associate sapphires with deep blue, they come in a variety of captivating colours, including violet, green, yellow, orange, pink and even colourless white—except for red, which is classified as ruby. This fascinating colour variation occurs due to trace elements within the crystal structure. Historically, they have symbolised sincerity, truth, and loyalty, making them a coveted choice for royalty and clergy. The name originates from the Greek word for “blue stone,” and ancient cultures believed that these gems could protect the wearer from harm. Fun fact: In addition to being the birthstone for September, sapphires are also celebrated for the 5th and 45th wedding anniversaries and serve as the zodiac birthstone for Capricorn. With their timeless beauty and rich symbolism, these stones are not just a birthstone; they are a treasured gem for all occasions.

The Stunning Spinel, The Birthstone Of August Next in prominence among August’s birthstones is spinel, a gem often mistaken for ruby due to its vibrant red shades, though it can also be found in blues, pinks, and purples. It is loved for its excellent hardness and brilliance, making it ideal for fine jewellery. Its name originates from the Latin word “spina,” meaning ‘thorn,’ referring to its sharp crystal edges. Remarkably, some famous “rubies” in history, like the Black Prince’s Ruby in the British Crown Jewels, are spinels, highlighting their sometimes-overlooked status. Fun Fact: It is sometimes called the ‘gem of immortality’ in various cultures, believed to confer eternal life and protection to its wearer. If you’d like to learn more about this birthstone for August, then please feel free to get in touch with the E.D.R team and we’ll be more than happy to help!

The name “peridot” is derived from the Arabic word “faridat,” meaning ‘gem.’ As August arrives, we celebrate peridot, the most recognised birthstone of the month, cherished for its vivid green colour reminiscent of sunlit leaves. It forms deep within the Earth’s mantle and is brought to the surface by volcanic activity, making it a unique gem associated with fiery origins. Table of ContentsWhat Is Peridot?Volcanic Origins: Where the Gem Comes FromThe Colour of the August BirthstoneHistory and SymbolismHow to Identify Natural PeridotCaring for Your Jewellery What Is Peridot? The gem is the transparent, gem-quality variety of the mineral olivine, a magnesium iron silicate that makes up a large part of the Earth’s upper mantle. It has a hardness of 6.5 to 7 on the Mohs scale, which makes it suitable for earrings, pendants and occasional-wear rings, though it needs a little more care than sapphire or diamond. One of its most distinctive optical features is strong double refraction. Look closely through the table of a larger stone with a loupe and you will often see a doubling of the back facet edges – a quick and reliable identification clue for gemmologists. Volcanic Origins: Where the Gem Comes From Interestingly, it is often found in association with diamonds, as both can be brought to the surface through the same volcanic eruptions in kimberlite and basalt deposits. However, they do not grow together; rather, they originate from similar deep-earth environments and occasionally appear in the same geological formations. Historically, the most celebrated source was the island of Zabargad (St John’s Island) in the Red Sea, which supplied the ancient Egyptians. Today, the finest large stones come from the Mogok region of Myanmar and from Pakistan’s Kashmir region, while the majority of commercial material is mined on the San Carlos Apache Reservation in Arizona, USA. A few remarkable crystals have even arrived from space, found inside pallasite meteorites. The Colour of the August Birthstone Fun fact: peridot is one of the few gemstones that occur in only one colour, green, though it ranges from yellow-green to olive depending on iron content. Unlike many coloured stones, its colour comes from the iron that is part of its basic chemistry rather than from a trace impurity, which is why it is described as an idiochromatic gem. The most valuable shade is a pure, saturated grass green with no brown tint. Because the gem looks equally vivid under daylight and artificial light, it was known as the “evening emerald” in antiquity. History and Symbolism Historically, this gem symbolises strength, protection and healing, prized since ancient Egyptian times as the ‘gem of the sun.’ Some historians believe that at least part of Cleopatra’s famous emerald collection was actually peridot, and medieval crusaders brought stones back to Europe where many were set into church treasures, including the Shrine of the Three Kings in Cologne Cathedral. It shares August with two other birthstones: spinel and sardonyx. You can explore the full year of gems on our birthstones page. How to Identify Natural Peridot Under the microscope, natural stones frequently show characteristic “lily pad” inclusions – small, disc-like stress fractures surrounding a tiny crystal of chromite. These, together with the strong doubling mentioned above and a refractive index of around 1.65 to 1.69, allow a gemmologist to separate the gem from look-alikes such as green glass, green tourmaline and synthetic spinel. The Gemological Institute of America (GIA) notes that the gem is rarely treated, which makes it a refreshingly straightforward purchase. Caring for Your Jewellery Clean gently: use warm soapy water and a soft brush; avoid ultrasonic and steam cleaners. Avoid acids and sudden heat: the gem can be attacked by acids and may crack under thermal shock. Store separately: keep it away from harder gems such as sapphire and diamond, which can scratch it. Choose protective settings: bezel or halo settings help protect the stone in rings worn every day. Whether you are buying a gift for an August birthday or adding to a collection, a report from an independent laboratory confirms that your stone is natural and correctly described. Contact E.D.R – European Diamond & Gemstone Reports in London to have your peridot examined and certified.

As a reputable gemmological laboratory based in London, we strive to inform and protect consumers in the gem-buying market. One of the treatments you may encounter when purchasing rubies is glass filling (also known as lead glass filling), designed to enhance the stone’s appearance and clarity. While this treatment can make a ruby look more appealing, it also raises serious questions about authenticity, durability and long-term value. Table of ContentsWhat Is Lead Glass Filling Treatment?3 Signs of Glass Filling in RubyWhy You Should CareGlass Filling Versus Other Ruby TreatmentsThe Importance of Certification What Is Lead Glass Filling Treatment? Glass filling, or clarity enhancement, involves introducing a glass-like substance into the fissures and inclusions of a ruby to improve its visual appeal. The process begins with heavily fractured, low-grade corundum that would otherwise be unsaleable. The material is cleaned with acid, then heated with a powdered glass that has a very high lead content. The lead glass melts, flows into every crack and, because its refractive index is close to that of ruby, the fractures all but disappear. This process is often conducted to mask imperfections, allowing lower-quality rubies to appear more valuable. The treatment first appeared in volume around 2004 and quickly flooded the market, so it is now one of the most common issues we see when examining rubies for valuation. While this technique can enhance the gem’s clarity and colour, buyers must understand its implications. 3 Signs of Glass Filling in Ruby When evaluating rubies, particularly those that appear unusually vibrant or eye-clean for their price, look for the following signs that may indicate treatment: Visible bubbles: one of the most telltale indicators is the presence of flattened gas bubbles trapped within the glass-filled fractures. These bubbles can vary in size and are often visible under 10x magnification. (Do not confuse them with the round gas bubbles seen in synthetic ruby, which sit in the crystal itself.) Yellow and blue flashes: look for flashes of colour that may indicate the presence of glass. These appear as the stone is tilted, along the planes of the filled fractures. Check whether these flashes reach the surface and look for any visible fractures on the external part of the ruby, as this is where the glass is introduced. Blue-green fluorescence: rubies, due to their high chromium content, typically fluoresce weak to strong red under UV light. When glass treatment is carried out, the glass itself can produce an unusual chalky blue to green reaction in the filled areas. Under higher magnification a gemmologist may also see a “flow structure” in the glass and, on the surface, a slightly different lustre where polished glass meets polished corundum. The Gemological Institute of America (GIA) has published extensively on these identifying features. Why You Should Care The presence of glass filling can significantly affect a ruby’s valuation. Treated stones are worth a small fraction of their untreated counterparts – often just a few pounds per carat – even though they may look impressive at first glance. Many trade bodies consider heavily filled material to be a composite rather than a genuine gemstone, and it must be sold with full disclosure. Durability is the other concern. Lead glass is far softer than corundum and is attacked by common household chemicals, lemon juice and even some jewellery cleaners. Repairs that involve heat, such as re-tipping a claw, can cause the glass to melt or turn cloudy. Additionally, repairs or restoration may permanently alter the appearance and longevity of the gem. Glass Filling Versus Other Ruby Treatments Not every treatment is equal. Traditional heat treatment is stable, permanent and widely accepted; minor residues of flux or borax in healed fractures are also commonly encountered. Lead glass, by contrast, is a bulk filler that can make up a significant proportion of the stone’s weight, which is why laboratories describe such material differently and why the price difference is so dramatic. The Importance of Certification Before making any purchase, ensure you obtain a valid report from a reliable, independent gemmological laboratory. This will provide transparency regarding the ruby’s treatment history and authenticity. At E.D.R – European Diamond & Gemstone Reports, we employ advanced testing techniques, including Fourier Transform Infrared Spectroscopy (FTIR), alongside microscopy and UV examination to accurately identify treatments like glass filling, and we state the result clearly on our Loose Gemstones Report. Remember, a well-informed buyer is empowered to make the best investment decisions. In conclusion, buy rubies with caution. Stay informed about the treatments available and always seek professional guidance. By doing so, you ensure the integrity of your precious gems and protect your investment for years to come. Contact E.D.R for expert analysis and assurance regarding the quality and authenticity of your gemstone purchases, or read more about the July birthstone, ruby.