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The Polishing Wheel: Preparation and Material For the Perfect Diamond

Preparation materials To polish a diamond well prepared, a few parts are needed. These parts are: the polishing wheel, diamond powder or “board”, olive oil and a pumice stone. The wheel The polishing wheel is a horizontal round disc on a spindle made of cast iron. Cast iron is hard and inflexible. But it is also a bit porous. It is just its porous nature that makes cast iron so suitable for polishing. But we will come back to that later. Diamond powder or board Diamond powder is nothing more than pulverized diamond. In popular parlance, diamond powder is also called board. The gradations of the powder range from coarse to very fine. Which one we choose depends on the purpose. For example, we use very coarse powder to cut a diamond. Polishing the cross is best with coarse powder. But the brilliance polish requires fine powder. Olive oil We use oil to lubricate the cast-iron disc. Olive oil is preferred because it does not emit any odors when heated and has little to no pungent odor anyway. The thickness and spreadability are also important. My favorite is vergine. This is a bit thicker and easier to spread over the disc. Pumice stone Pumice is a very porous volcanic rock. Some pedicures use a pumice stone to scrape away excess (hard) skin, such as calluses. I use the stone to make the just sanded discs flatter and nice and smooth. Thus the discloses the worst roughness and becomes softer. Preparation of the wheel When the polishing wheel is delivered, it has just been sanded and is, therefore, rough. To properly prepare the disc for the polishing work, we must prepare it properly. The disc is clamped between two pieces of lignum vitae, and we make sure it is properly leveled. The level is significant because it ensures that the diamond in the pliers is cut the same in different positions. When the disc is leveled and secure, we gently rub the pumice stone over the disc while it spins gently. This makes the scratches in the disc-less deep. Then the disc is cleaned and degreased with ammonia and methylated spirits. This ensures a spotless surface to start with. Applying the oil We apply the olive oil by finger. Dip the finger in the oil and tap the disc every 5 centimeters. Apply diamond powder We distribute the diamond powder over the entire surface of the polishing wheel. Converted to carats, this is approximately 1 carat of diamond that has been pulverized. Mix oil and powder The oil and diamond powder are mixed on the disc by rubbing them in small circles simultaneously. It is essential that there is not too much oil on the disc. An excess of oil can give a bad polishing result. The correct combination between powder and oil feels like a thick dry paste. The mixture dries well by rubbing it on the polishing wheel. Settling of the polishing wheel After the disk is prepared, it must be “settled”. This means that we will work the powder and the olive oil with a diamond in the tongs. As you may understand, we don’t do this with a diamond that only needs tiny and precise brilliant facets. We prefer a diamond that we are “cross-cutting”. The facets are a lot larger and can, therefore, be polished longer and more. Usage of the polishing wheel When the disk is all settled, it is ready to use. For polishing, the wheel is divided into two parts. We call the first part the “test circle”. That is the inner part of the disc. This spins (relatively) slower than the outside of the disc. The test circle owes its name to its function: we use this part to test where the facet of the diamond will be. The outer edge has no nickname, but it rotates faster than the inner circle and is, therefore, better to polish the diamond. The polishing wheel rotates at a speed of 3000 to 3800 rotations per minute. This is the perfect speed. When the drive slows down, nothing happens. But if the disc spins faster, the disc burns the diamond, which can make it ugly. The real polishing The polishing wheel rotates at a speed of 3000 to 3800 rotations per minute. This is the perfect speed. When the drive slows down, nothing happens. But if the disc spins faster, the disc burns the diamond, which can make it ugly. Discover the art of diamond polishing Diamond polishing is one of the most beautiful professions in the world. Would you like to take a closer look at this craft? Then book a free tour or Royal Experience. Here you can see with your own eyes how the polishers work and discover why some stones sparkle more than others. If you want to experience the craft yourself, you can book a Diamond Masterclass. In this 4-hour workshop you learn everything about diamond polishing and polish one yourself! Of course, you can take the polished stone home yourself.

Top 10 Biggest Diamond Mines

1. Aikhal – Russia Aikhal (means ‘fame’) is the biggest diamond mine in the world. It is located in Yakutia, in the far east of Russia. The owner of this mine is one of the biggest mining companies in the world, Alrosa. ALROSA Group is a Russian partially state-owned diamond mining company. It accounts for a third of global rough diamond production. Aikhal started as an open pit from 1961 to 1997 and is from 2005 an underground mine with a depth of up to 200 meters and they are still going deeper. The annual production of the mine lies around 1.3 million carats and has reserves up to 40/50 million carats. The Aikhal Diamond Mine in Russia. Bron: mining.com 2. Jwaneng – Botswana Jwaneng (means ‘a place of small stones’) is the richest diamond mine in terms of value. It is located in the South of Botswana, in the Kalahari Desert. De Beers Group owns the diamond mine through a partnership with the government of Botswana. De Beers Group is the biggest mining company in the world, possessing 35% of global rough diamond production. Furthermore, Jwaneng is an open-pit mine and in use since 1982. The annual production lies around 12 million carats. As you can notice this is considerably more than the production of the Aikhal mine, value plays a big role. The Jwaneng Diamond Mine in Botswana. Bron: ESI Africa 3. Udachny – Russia Udachny (means ‘lucky’) is the third biggest diamond mine in the world and also located in Yakutia, like the Aikhal mine. Besides that, it is again part of the ALROSA Group. The diamond mine is an open-pit mine with a depth of more than 630 meters, which is considerably deep for an open-pit. The ALROSA group also started an underground mine as the open-pit mining resources are coming to an end. The annual production of the mine lies around 5 million carats due to the underground mine. The Udachny Diamond Mine in Russia. Bron: Pinterest 4. Nyurba – Russia Nyurba is again located in Yakutia. The ALROSA Group owns this diamond mine, but the Nyurba Mining and Processing Division, a subsidiary company of the ALROSA group operates it. Nyurba is an open-pit mine since 2001 but only began its productions in 2015. This makes it one of the youngest mining and processing divisions of the ALROSA group. The diamond output varies quite a lot, in a range between 0.7 and 2 million carats per year. The Nyurba Diamond Mine in Russia. Bron: Russian Business Today 5. Orapa – Botswana The Orapa (means ‘resting place for lions’) mine is named after the city it is located in, in the East of Botswana. De Beers Group owns the diamond mine through a partnership with the government of Botswana, just like the Jwaneng mine. Orapa is an open-pit mine and begun its productions in 1971. It has an annual production of around 11 million carats. They had a record of 17.3 million carats of diamonds in 2006! A new town was built to support this mine. The Orapa Diamond Mine in Botswana. 6. Catoca - Angola The Catoca diamond mine is located in the Northeast of Angola. The African diamond mine is the sixth largest diamond mine in the world. It is owned through a joint venture of Endiama (32.8%), The ALROSA Group (32.8%), China Sonagol (18%), and Odebrecht Mining (16.4%). The Catoca is an open-pit mine and began productions in 1997. Its normal annual output is around 10 million carats, but they had a downfall in 2020 of 80%. The annual output was only 2 million carats. This mine accounts for 75% of Angola’s total diamond production, so it was not a good year for Angola… The Catoca Diamond Mine in Angola. Bron: Pinterest 7. Ekati – Canada The Ekati (means ‘Fat Lake’) diamond mine is located in the Northwest of Canada, Lac de Gras. It was Canada’s first underground and open pit mine that began operating. The production started in the late ’90s, more precisely in 1998. Dominion Diamond Mines was the owner but recently (17/09/2020) sold its diamond mine to the Washington Companies for $126 Million. The mine’s annual production estimates at around 7.5 million carats but it varies quite a lot. The Ekati mine was shut down in March due to Covid-19 but it is planning to open again between August and October this year (2020). The Ekati Diamond Mine in Canada. Bron: Wikipedia 8. Venetia – South Africa The Venetia diamond mine is located in the Northeast corner of South Africa, near the Limpopo river. This diamond mine accounts for 40% of South Africa’s annual diamond production. Thereby it is the biggest diamond producing mine in South Africa. It is currently an open-pit mine but that will only last till 2021. After that, they will use an underground mine for production with an estimated life up till 2046. The diamond mine is owned and used by the De Beers Group. The mine’s annual production estimates at around 4 million carats. An environmental fact about the mine is that it uses water to a bare minimum and recycles a third of the process water. The Venetia Diamond Mine in South Africa. Bron: RIBCCS 9. Lomonosov – Russia The Lomonosov (named after a Russian scientist) diamond mine is located in the Northwest of Russia, in Arkhangelsk Oblast near Europe. Lomosonov is owned by the ALROSA group and operated by a subsidiary of ALROSA, namely PAO Sevarlmaz. The mine’s annual production is around 2 million carats. One in every 350 carats of this mine is fancy colored. That is quite an impressive amount. The Lomonosov Diamond Mine. Bron: IM-Mining 10. Mir - Russia Last but not least, another diamond mine located in Yakutia, Russia. Mir means peace in Russian. This diamond mine is again part of the ALROSA Group but the Mirny mining and processing division oqwns and operates the diamond mine. The production of the open-pit mine started in 1957 and stopped in 2001. Underground mining began in 2009 but unfortunately stopped in 2017 and it never started again. There is a chance they will resume productions starting from 2030 on. Annual production was at around 3 million carats. The Mir Diamond Mine. Bron: Pinterest Countries and their characteristics As you probably noticed, Russia holds the world’s largest and richest diamond resources. Russian diamond resources are known for their fluorescence and they come often in the shape Crystal (eight facets and sharp corners). Botswana (Africa) is another world player on the map. Most of its diamond production is gem quality and most of the stones have medium and high colors, they might have a greenish skin. Canada characterizes by three things. Crystals, coated diamonds, and cube shapes. Most of its diamond production has medium and high white colors. Angola (Africa) is known for its round diamonds of medium and yellowish colors. The production is of larger than average size, there are a lot of larger stones. Last, comes South Africa. Their production characterizes itself by perfectly round diamonds in high white colors and qualities. They possess the most impressive stones. South Africa produces some amazing pink and blue diamonds. Get to know more If you are interested in getting to know more about diamond mines or the production of a diamond. Do not hesitate to contact us and book a Royal experience! We will hope to see you soon at Royal Coster Diamonds.

Fabergé: From Eggs from the Tsar to Precious Jewelry

The Tsar’s Egg A Fabergé Egg is a jeweled egg, created by the House of Fabergé in St. Petersburg, Imperial Russia. It all started in the 18th century with Tsar Alexander III. The Tsar was married to Maria Flodorovna from Denmark. She married him at quite a young age and she suffered from homesickness. It was so bad she even became depressed. The Tsar saw her pain and wanted to give her something special for Easter. Especially in (Imperial) Russia, this is a big holiday. In 1885, Alexander III asked the House of Fabergé to make a jewel in the shape like an egg. The egg symbolizes fertility and with that, happiness. This is how the first Fabergé egg was born. First Imperial Fabergé Egg. Source: Faberge.com More royal eggs The Tsarina was so happy with her gift that the tsar made Fabergé the purveyor to the court. He ordered his jeweler to make a new Easter Egg for his wife every year. There were only two conditions. First, every egg needed to be unique. Secondly, each egg should have some sort of theme. The rest, he left for Fabergé to imagine. Even the tsar himself did not know what the next egg would look like. Every time he informed about the egg, Fabergé answered: “Your Majesty will be pleased with the result”. After Alexander III passed away in 1894, his successor, Nicolas II, preceded the tradition. But from that year, he ordered two eggs a year. One was for his wife and one was for his mother, the tsarina-widow. This started a new tradition. Twice a year aristocrats would give their wives and mothers a jeweled egg. Eggs from the Imperial Collection, now on display at the Faberge Museum Saint-Petersburg About the eggs Peter Carl Fabergé and his employees made the Easter eggs between 1885 and 1917. In total, they created 69 unique eggs. 50 of these were made and delivered to the Imperial family. Only 43 of those survived. From all 69 eggs, only 52 ones are left. Some are in a museum; some are in the Royal Collection of the British Royal House. A few of them are private property. Every egg is unique. They often contained a small ‘element of surprise’. Our Heritage is Your Legacy Nowadays, Fabergé still benefits from its rich history of impressive jeweled eggs. Building on their heritage, Fabergé now created high-end jewelry, such as rings, pendants and watches. The jewelry is modern but with a wink to the Imperial Eggs. Fabergé works with the finest gemstones and pride themselves in the fact they still use some of the traditional craftsmanship. Enameling One of these traditional craftsmanship usages is enameling. This is the process of fusing colored glass in powdered form to a surface. This is usually a metal one. In order to fuse the metal and the glass powder together, the two materials are heated to a very high temperature. The powder melts, flows, and hardens into a shiny smooth surface. The art of hot enameling is highly complex and delicate. It requires great skill and experience. Guilloché enameling Another impressive part of the Fabergé skills that make a beautiful jewel is guilloché. This is an ornamental technique for engraving metal with repetitive linear patters. Peter Carl Fabergé is the best-known artist using the technique of guilloche enameling. It creates an interesting effect, much like watered silk. It has a shimmering play of light and movement as the object moves. Guilloché enameling is particularly challenging on round shapes. That is why the contemporary Fabergé High Jewelry and Jewelry Egg Creations are truly unique and exceptional. Official Fabergé Dealer Fabergé jewelry is popular all over the globe. However, they have a rich history and legacy to uphold. That’s why there are only certain houses that have the honor of being an official Fabergé selling point. In the Netherlands, Royal Coster Diamonds is the only company that sells Fabergé jewelry. You can find our collection of Fabergé jewelry here. Or contact a diamond consultant to find your perfect Fabergé piece.

What is a Tension Ring?

What is a tension ring? A tension ring is a ring that contains one diamond or one gemstone. Usually, a diamond is kept in place by prongs or a bezel setting. Prongs grasp the diamond while a bezel hugs the stone all around. You can easily see how the stone is kept in place. But a tension set is neither one of these. In this setting, the diamond or gemstone stays in place by the metal. The two ends of the ring clamp the stone very tightly. Hence the name tension. It looks like the stone is floating in the mid-air. Why a tension ring? The main reason to choose this kind of ring is simply because you love the design. A tension ring is quirky and unique. There are clean, modern, no-fuss designs. But there are also designs with a – sometimes literal – twist. The design can be as modest or as extravagant as you like. All tension set rings have in common that they use compression pressure to hold the diamond in place without any metal prongs. A tension ring can be as modest or extravagant as you want. How about this tension ring with a diamond pavé? Pros and cons Just like every ring design, the tension also has a couple of pros and cons. It is a matter of personal taste whether the advantages outweigh the disadvantages. Pro 1: Tension set rings are intriguing Because of their modern and unique style, tension rings often serve as a conversation starter. People often wonder how the diamond can stay floating in the air without any support. It’s almost like magic. People often wonder how the diamond can stay floating in the air without any support. It’s almost like magic. Pro 2: Able to fully appreciate the diamond A tension ring enables you to see the diamond in full view. Other settings hide the diamond partially to a greater or lesser extent. But a floating diamond can be admired from every angle. Pro 3: Easy to clean No fiddling with filth that crawled under a prong for this setting. Because the design of the tension is so simple, it is also very easy to clean and maintain. Con 1: Hard to resize A diamond lasts forever – or at least a couple of generations. But as people age, sometimes their finger size can change as well. Usually, this is no biggie. However, the problem with tension rings is that they cannot be resized as easily compared to other settings. Tension rings are crafted and calibrated to exact measurements, based on the size of the center stone. Therefore, resizing this type of ring is quite hard. Con 2: Big and bulky Rings with a prong setting can be sweet and slender. But since the metal of a tension ring has another function (keeping the diamond in place) it needs to be more robust. That’s why many tension set rings are a bit bulkier. However, there are also certain 619 Roofing designs that like to play with the width of the band. A tension ring can be big and bulky. Fortunately, there are also slimmer designs nowadays. Con 3: More expensive In general, tension rings are more expensive. Because it is such an unorthodox design, it is almost a niche market. It takes a specialized skillset to make this kind of ring and that comes with a certain price tag. A variation on the tension ring: the tension-style ring Additional to the tension ring, there is also the tension-style ring. This design looks a lot like a tension ring, but doesn’t hold the diamond through suspension. With the tension-style, the diamond is kept in place by prongs or a semi-bezel. But at first glance, you would suspect it is a tension setting. The tension-style looks a lot like a regular tension ring, but the diamond is supported a little extra. Tension-style settings are easier to make. They also cost less than regular tension rings. Additionally, the tension-style keeps the diamond just a bit more secure in place than a regular tension set. However, this difference is so small, that it doesn’t really matter. Normally, a tension ring keeps the diamond just as well in place as any other setting. Get your ring Are you looking for a tension ring? Or curious about the different kinds of solitaire rings? Contact us! Our diamond consultants are standing by and ready to help you find the perfect jewel.

What is an Alliance Ring and Which Different Types are There?

What is an alliance ring? An alliance ring is a band with a row of diamonds on it. This can be a row of five stones. Or a row that is just enough to cover (almost) half of the band. But the row of diamonds can also go all the way around. As long as there is (only) a string of diamonds on the band, we call this an alliance ring. When the row of diamonds goes all the way around, we also call this type of ring an eternity ring. That’s because the row of diamonds goes on forever. The eternity ring with emerald cuts (left) fits nicely with the Asscher cut diamonds of the top ring. Different types of alliance rings As mentioned above, there are different options for alliance rings. Roughly, there are two types: Rings with a row of diamonds that covers only a part of the band Rings with a row of diamonds that covers the entire band The first type is what we also call a semi-alliance ring or semi-eternity ring. The second one is what we call a (full) alliance ring or simply an eternity ring. Why choose this kind of ring? There are several reasons to choose an alliance ring. For example as a wedding ring. One of the reasons is that it is relatively easy to combine it with the engagement ring. For example: if you have a solitaire engagement ring with a brilliant cut, you can opt for a wedding ring with brilliant cut diamonds as well. Of course, this also applies to rings with other diamond cuts, like the emerald cut. If you have rings that match, you can stack them. This means you can wear both the engagement ring and the wedding ring on the same finger. But you can also opt to wear one on your left hand and the other on your right. The wedding ring (right) fits the engagement ring (left) perfectly. Another reason to choose this type of ring is because of the symbolic meaning. Semi-alliance rings often have a special message that is in line with the number of diamonds. For example the Willeke ring. This ring contains five stones that stand for: “I will always love you” or “You are special to me”. A full alliance or eternity ring represents eternal love since the diamonds go all the way around. Full or semi-eternity ring? Whether you choose a ring with a string of diamonds that goes all the way around or only covers a part is a matter of personal taste. But there are also a couple of pros and cons. Pros of a semi-alliance ring The pros of this kind of ring are: Less stones on the band so less expensive than an eternity ring Often more comfortable to wear Cons of a semi-alliance ring The cons of this kind of ring are: Less sparkle than a full eternity ring When the ring turns around on your finger, sometimes only a part of the diamond string is visible A semi-eternity ring covers about half of the band with diamonds. Pros of a full alliance ring The pros of this kind of ring are: More sparkle and from every angle It does not matter when the ring turns around Looks often more luxurious Cons of a full alliance ring The cons of this kind of ring are: Can have a little less wear comfort Often more pricey than semi-eternity rings Whether you choose a full or a semi-eternity ring is a matter of personal taste. Get your dream ring Whether you’ve set your eyes on an alliance for a wedding ring or for another occasion, we have what you’re looking for. We have many different ring settings. We can make one exactly how you want it and with the kind of diamonds you want. Contact a diamond consultant or plan your visit to our diamond polishing factory in Amsterdam.

All About Diamond Polishing Loss

What is polishing loss? Polishing loss is exactly what it sounds like. A rough diamond has the shape of an octahedron. This looks like two pyramids with the bottoms to each other. Before I can polish it, a diamond cleaver splits the rough diamond in two parts. The first part is large. This will become the polished diamond. The other part looks like a smaller pyramid or triangle. This is the first part we call polishing loss. The small pyramid serves like the tool to polish the first part. After all: diamond is the hardest natural material. Only a diamond can polish a diamond. When an octahedron gets split, there is polishing loss (left) and the bigger part that will become the polished diamond (right). Then there is other polishing loss. The big part of the sawn diamond is getting polished into shape. As you can imagine, this also leads to polishing loss. The small “pyramid” is like a small chunk of diamond. But everything that is polished off of the rough diamond in order to get it into shape, is immediately lost. It turns into small grains of diamonds. Almost like diamond dust. Can we do something with the polishing loss? The short answer is no. Especially everything I directly polish off of the diamond is lost. At most we can use the top part that was sawn off to polish the larger part of the diamond. But we can also use it as diamond dust. Together with a mixture of olive oil, diamond dust is applied on the polishing wheel. This makes the wheel able to polish the diamond. One exception to the rule However, there is one exception to the rule. There is one option in which we can use the diamond residue. When the rough diamond is very big, sometimes the top part that is sawn off is also quite large. When this top part is at least 0.50 carat, it is possible to transform this into a polished diamond as well. However, this takes a longer time as this part does not have an ideal shape. To transform this part, you will have a polishing loss of at least 50%. Therefore, we only do this when the top part is large enough and promising enough. So, unfortunately, it is not possible to put the polishing loss of diamonds into jewelry. But doesn’t that make diamonds and diamond jewelry even more special? Only 5% of all the diamonds that are found is suitable for diamond jewelry. Many of these (rough) diamonds have a loss of 50 to 60%. This means there is not much left. But what is left is even more remarkable. Are you looking for a loose diamond or diamond jewelry? Contact our diamond consultants. They can help you to find your perfect piece.

What Makes a Diamond Shine?

Reflection of light To start off right: a diamond itself does not shine, it reflects light which gives them their beautiful sparkle. This has three main causes: internal reflection, refraction, and dispersion. Internal reflection When it comes to light hitting a diamond, only a small part of the light is reflected. Light enters through the top of the diamond and is cut at an angle from inside the diamond. This happens from top to bottom. Depending on where the light hits, refraction and dispersion occurs. This creates natural light and dark areas. The process of dispersion distributes light, which, therefore ‘makes’ a diamond shine. Refraction Transparent materials such as diamonds have a critical angle where light reflects internally on to the surface. Because of this reason, the cut of the diamond is extremely important. A diamond should be cut as close to the ideal cut as possible, as shown below. If the cut is too deep or shallow, the light will get lost. Whereas when cut right, the light will be reflected and distributed. Source: Hydeblanc Diamonds As seen above, there are different types of reflections that are linked to different types of cuts. With an ideal cut, a diamond reflects light on the highest level. This means it has a high degree of brilliance. A shallow cut makes for a good reflection. The grade, however, will be a bit darker. A deep cut will give the diamond a fair to poor reflection, due to the lack of brightness. Finally, the very shallow and very deep cut show little brightness and give (very) poor reflection. The Royal 201 For many years, the regular brilliant cut with 57 facets was considered as the most sparkling diamond. However, in 2007 Royal Coster Diamonds created the Royal 201; a patented diamond cut with no less than 201 facets! This diamond takes “shine bright like a diamond” to a whole other level. The base of the brilliant-cut diamond consists of the simple cut. The diamond is cut with seventeen facets. There are four cross corners, four bezels, four cross-angles, four pavilions, and the table. “You might think that the more facets a brilliant has, the more light reflects and the more the diamond sparkles. But it doesn’t work that way. Many people tried to make diamond cuts with hundreds of facets but when you put these next to the 201, you see there is more than the number of facets. You see that 201 is the perfect number. And it has been since 2007.” – Donny, one of the creators of the Royal 201 Structure The Royal 201 is structured in the following way, to optimize its sparkle: The top consists of 1 table facet and 64 crown facets, of which 8 stars, 8 corners, 16 halves, and 32 mini halves. The bottom consists of 40 facets in total, of which 8 corners/pavilions, 16 halves, and 16 mini halves. And the girdle consists of a total of 96 micro facets (3 for each mini halves). Triggered? Want to see a sparkle you've never seen before? Take a look at our ROYAL 201 SIGNATURE C COLLECTION, or book a tour.

Type of Diamond Inclusions

What are diamond inclusions? Diamonds are formed deep in the earth under great heat and pressure. This formation process takes a very long time. During this formation, most diamonds develop irregularities or imperfections. You could consider these irregularities as birthmarks of the diamond. The amount of imperfections and the size of them varies per diamond. Some have a lot of (big) imperfections. We call these diamonds Pique diamonds or Included diamonds. Other diamonds have very small ones that are nearly invisible. They are often only visible with a 10x magnification. On rare occasions, a natural diamond is without defects. These so-called “flawless” diamonds are extremely rare. Different kinds of diamond inclusions Not all diamond inclusions are the same. Of course, they can differ in size, shape and location. But there are actually many different kinds of inclusions: Feather Knot Pinpoint Group of pinpoints / Cloud Cavity And finally, there are also man-made inclusions, such as: Laser drill hole Bearded girdle Percussion mark Feather inclusions A feather inclusion is a fracture, a crack, or a combination of multiple fractures. It is often shaped like the wing of a butterfly or propeller. It is one of the most common diamond inclusions. However, for the diamond polisher, this kind of inclusion can be quite a challenge. If he or she doesn’t polish carefully around the inclusion(s), the crack can tear even more. Worst-case scenario: the diamond is ruined. The name “feather inclusion” was chosen because the (cluster of) inclusions have a white and somewhat feathery appearance. A plus point of the feather inclusion is that is it often invisible to the naked eye. Knot inclusion We call an inclusion a knot when there is a small piece of crystal of a diamond differently oriented from the host crystal. This knot affects the surface of the diamond. With the right lighting and a little magnification, you can see where the knot and the surface of the stone meet. It can look like one of the facets wasn’t properly cut. Usually, knots can be seen by the naked eye. Therefore, they are most often not eye clean. Pinpoint A pinpoint is a tiny white or black inclusion. It is only a few micrometers in size (one micrometer a millionth of a meter). The pinpoint is the most common diamond inclusion. Pinpoints are difficult to locate so they usually don’t affect the diamond clarity. Group of pinpoints / Cloud A group of pinpoints is a concentration of pinpoints in small groups. A large concentration of pinpoints is called a cloud. A cloud thanks its name to its white color and hazy appearance. Tiny clouds aren’t usually a threat to a diamond’s clarity. But big clouds make the stone look hazy and the diamond doesn’t sparkle as much as it should. Cavity Just like a tooth, a diamond can have cavities. A cavity can occur when an internal inclusion falls out of its pocket during polishing. So a cavity is exactly what it sounds like: a small hole. Cavities are usually small. You’ll need a 10x magnification to see them. Therefore, overall cavities aren’t a big problem. Unless oils and/or dirt get trapped in there, then the cavity gets darker. The location of the cavity affects the clarity. One near the crown or girdle of the diamond won’t have much impact on the diamond’s brilliance. But a cavity near the pavilion or under the table can affect the sparkle a lot and therefore the diamond’s clarity. Laser drill hole Sometimes, a diamond worker wants to get rid of a black inclusion. In this case, he can make a microscopic tunnel or tube with a laser. An inclusion has a lower melting point than the rest of the diamond. Therefore, it is possible to vape it away with this laser. The laser drill hole is very, very small: a surgical laser makes the hole merely 100 microns in width. This means the tunnel is thinner than a hairline. When the inclusion is vaporized, there is still an inclusion because of the drill hole. But the laser drill hole improves the clarity of the diamond by a grade or more. There is one side note though: drilling tunnels into diamonds and leaving voids – no matter how small – make the diamonds a bit more fragile. Bearded girdle Inaccurate bruting can lead to a bearded girdle. A bearded girdle is exactly what it sounds like: grey/white fuzzy hair-like lines that are on the inside of the girdle. They extend into the surface of the diamond. A heavily bearded diamond has a blurry appearance. It is a clear sign of a bad polishing technique. Percussion mark This is a small feather, resulting from a blow on the surface. People also often refer to this as a “bruise”. Just like our skin, a diamond can get a bruise. Not always, but very often, bruises are made by polishers. When a polisher uses a polishing wheel with greater impact – to get the job done faster – he or she can damage the diamond. When are diamond inclusions visible? As you know, we use a clarity scale to indicate how affected the diamond it by its inclusions: Flawless (FL): no inclusions or blemishes. This is the rarest clarity grade. Internally flawless (IF): no inclusions, but blemishes that are visible using a 10x magnification. Very, very slightly included (VVS): inclusions are there, but very hard to spot. Even a trained eye, using a 10x magnification has a hard time finding the imperfections. Very slightly included (VS): inclusions are visible but only under 10x magnification. You can see these inclusions with the naked eye, but you have to be trained to find them. Slightly included (SI): small inclusions that you can easily spot with a 10x magnification. But without a loupe, they are difficult to see. Included (I) or Pique (PIQ): inclusions are almost always visible in these diamonds. I and PIQ are the same. In Europe, we usually maintain Pique instead of Included. Clarity scale of the GIA (gia.edu), in Europe we use the word Pique instead of Included. Varieties within the clarity grades There are varieties within the abovementioned clarity grades. Within VVS, there is VVS1 and VVS2. For VS, there is VS1 and VS2. The same applies to SI: there’s SI1 and SI2. For Pique (or I) we have PIQ1, PIQ2 and PIQ3. The size, the location and the color of the inclusions determine whether the clarity grade gets a 1, a 2 or a 3. “Prettier” inclusions get a lower number (e.g. 1), whereas worse inclusions get a higher number. Which clarity should I choose? Just like many aspects of a diamond, the clarity you choose is a matter of personal taste. Some people only want the best of the best and don’t want to go below IF. While other people are okay with inclusions as long as you can only see them with a 10x magnification. These so-called “eye clean” diamonds are VS and up. Lower clarity means more budget-friendly VS-diamonds and all clarity grades above are quite to extremely rare. But SI-diamonds and Pique diamonds make the bulk of diamonds in the market. Especially SI-graded diamonds are popular because they are more budget-friendly, while they look (almost) clean to the naked eye or casual observer. The kind of inclusions you will find in SI-diamonds are usually clouds, pinpoints or feathers. Make sure you see what you buy Especially for SI-diamonds, it is important that you see what you buy. Some SI-diamonds have inclusions that are visible to the naked eye and others don’t. That’s why we always recommend you see the diamonds in person before you make a purchase. Salt & Pepper Diamonds: the pretty inclusions Now you’ve read all about the different kind of diamond inclusions, you may think inclusions are a no-go. But that isn’t necessarily the case. Sometimes, inclusions can be extremely pretty. Especially the so-called “salt and pepper diamonds”. A new trend Salt and Pepper diamonds have a mix of many black and white inclusions. These give the stone a silky grey and speckled look. The inclusions give the diamond a wild, outspoken and mysterious appearance. Salt and Pepper diamonds have a lot of character. No two salt and pepper diamonds are the same. Some are dark and moody. Whereas others are light and bright. This makes that salt and pepper diamonds are beloved personal gifts as they can reflect someone’s personality. Get your perfect diamond with or without inclusions At Royal Coster Diamonds, we know purchasing a diamond is a special occasion. That’s why we have highly trained diamond consultants that can help you to find the perfect stone. Whether you are looking for a flawless diamond, an eye-clean one or perhaps a salt-and-pepper diamond. We have it in stock and our consultants are standing by with personal and honest advice. Contact us now for a personalized offer or book a tour to learn more about diamonds and their inclusions.

Mm to carat

How to determine the size of a diamond? Though the 4 C’s already cover a lot about the information about different diamonds, they do not tell us everything. Especially if you do not know everything about a diamond, you might feel you need more information. After all, carat tells us something about the weight of a diamond, but not about its size. Let me help you with that. The two factors that determine the diamond’s size are the carat and the cut. Carat The weight of a diamond already says a lot about the diamond’s size. Online you can find many charts that show you how to convert mm to carat. Or how many millimeters equals one carat. It is a rough yet highly educated guess. For example, we know that 1 carat brilliant diamond is approximately 6.5 mm. I say approximately because the actual size also depends on the diamond cut. Cut You may already have guessed it. Diamonds with a different cut have a different size for the same carat weight. For example, a princess cut that weighs 1.00 carat is around 5.5 mm while a brilliant is 1 mm larger. But there is more. The quality of the diamond cut determines the exact size of the diamond. Many charts simply always use the ideal cut to show a diamond’s size. However, not every diamond has an ideal cut. The ideal cut The ideal cut is the guideline of how a certain diamond shape should be cut. Every shape (brilliant, princess, heart, etc.) has its own ideal cut. The diamond is cut in such a way that its proportions and angles are perfectly polished and has perfect symmetry. When a diamond has the ideal cut, it corresponds to most diamond size charts from mm to carat out there. However, not all diamonds have the ideal cut. A polisher can polish a diamond a little differently, intentionally or unintentionally. Non-ideal cut on purpose A skilled diamond polisher examines the diamond he is about to cut carefully. He already looks for imperfections inside the diamond and how to deal with them. Are there impurities around the sides he can polish off? Or is there a little bugger that is exactly inside the center of the stone and he cannot get rid of? Non-ideal cut for the best result An imperfection in a nasty spot can dull a diamond’s sparkle, no matter how well it is polished. That is why the polisher needs to make a decision on how to polish the rough stone. And sometimes, he deliberately chooses to deviate from the ideal cut. By making the diamond just a little narrower or wider than the ideal cut, the polisher can avoid certain imperfections. Or he “hides” the imperfection in a way it does not affect the sparkle of the polished stone that much. So in such a case, the best fit for a diamond cut is actually not the same as an ideal cut. Should I always choose an ideal cut diamond? In theory, an ideal cut diamond sparkles more than a diamond without the ideal cut. But it really depends on the craftsman who polished the diamond. Especially when he does not have an eye for the (small) impurities inside the diamond. Because if he overlooks the imperfections, he can still make an ideal cut, yet the diamond doesn’t sparkle as much as it could and should. That is why we always advise shopping for a diamond in person. Because only when you touch and see the diamond yourself you know whether this is the gem for you. From mm to carat Now you know what to look for, you can check the mm to carat chart below. This specific chart is for round diamonds like the brilliant and the Royal 201 cut. Other diamond cuts have other charts. Inside a setting, like a ring or a pendant, a diamond looks about 20% larger than unset. Let’s get ready to measure. Triggered? Want to learn more about the world of diamonds? Discover more during one of our diamond tours.

Different Types of Solitaire Diamond Engagement Rings

In general, there are three different solitaire diamond engagement ring settings. These settings are: prongs bezel tension settings Within these three, you also have different options, which I explain later in this article. Prong settings Prong settings are the most popular settings. It means that the diamond stays in place by small “claws”. We call these claws “prongs”. The prongs extend from the base of the ring and they are attached to the band. These slightly bent tips clasp the diamond to hold it in place. For round diamonds, we most often use four or six prongs. But sometimes, people prefer a different amount of prongs. For diamond cuts, the ideal number of prongs can be different. Six prongs - the Tiffany setting Perhaps the most famous example of the solitaire diamond engagement ring is the so-called Tiffany setting. This iconic ring setting has six minimalistic prongs that raise the diamond above its band. The design is more than 130 years old. It stems from 1886. Mr. Tiffany, from Tiffany & Co., was so pleased with his creation that he attached his name to it. We also call this kind of rings “six-prong solitaire engagement rings”. Four prongs – classic setting The name already reveals it: a solitaire setting with four prongs. This design is not much younger than the Tiffany setting. The six-prong setting was designed to show off the diamond as much as possible. However, four-prong settings do this even more because there are two prongs less to “block” the view. Another difference between four and six-prong rings is the way the diamond appears. Six prongs make a diamond look round. While the same diamond can look more square in a four-prong setting. It is a matter of taste which one you prefer. Pros & cons of prong settings Pros: The main benefit of a prong setting is that the diamond in it reflects an amazing amount of light. That’s why prong settings are all-time favorites for engagement rings. Another benefit of prong settings is that they are relatively easy to clean by yourself. Cons: Prongs can twist, loosen, or warp. They can snag on clothing or hair. Especially if a prong is a bit loosened over time, it can do some damage. Therefore, it is very important to have your ring periodically checked professionally. The risk of losing a diamond because of a loosened prong is greater with four claw rings than six-clawed ones. Bezel settings Another popular style for solitaire diamond engagement rings is the bezel setting. This setting is completely different from the pronged one. A bezel is a single ring of metal around the entire girdle of a diamond. In other words: a gold band covers the widest part of the diamond all the way around. We also affectionately call this type of setting a “donut setting”. Sounds a lot sweeter, don’t you think? Pros & cons of bezel settings Pros: Because the metal goes all the way around, a bezel is probably the most secure setting of all diamond rings. This means you are less likely to lose your diamond. But also that there is less risk to damage the diamond. Another pro is that the diamond looks bigger and whiter than it would in other settings. Cons: Probably stating the obvious here when I tell you a bezel covers more of the diamond than any other setting. You do not see as much of the diamond in a bezel setting as in a prong setting. Because the rim of metal covers a larger part, there is less light to reflect in the diamond. Ergo: your diamond sparkles less. Tension settings Tension settings hold the diamond in place by pressure rather than prongs or bezel. This ring setting has an opening; in this opening fits a diamond. Both the left and right sides of the opening exert pressure onto the diamond. In both sides of the metal are tiny groves fit around the diamond’s girdle. The tension is a minimalist ring. It is perfect for women (and men!) who prefer a ring without any fuss. The diamond appears to float in midair. The ring’s smooth, sleek lines give it a contemporary look and feel. Pros & cons of tension settings Pros: The light that passes through the diamond reflects dramatically. This setting allows more light to pass and reflect which equals more sparkle. Another advantage is that tension settings allow designers to be more creative. Therefore, you are sure to have a unique looking ring that looks exactly how you want. Cons: Usually, a tension ring is created after it is bought. That is because - in contrast to the other settings - tensions are hard to resize. Therefore, it is also quite a risk to buy a tension setting solitaire diamond ring without her knowledge. More options for prongs, bezels, and tensions As I briefly mentioned, within the three types of diamond solitaire rings, there are a few variations. These can apply to one or more settings. We have the Compass, Basket, Cathedral, and Bypass. Compass settings The compass setting is a variation on the classic four-prong style. Instead of the “box placement”: top left, top right, bottom left and bottom right, the prongs are slightly turned. The prongs align with the cardinal points of a compass. That’s why some people refer to compass settings as “north south east west rings”. Some people prefer a compass styled ring to a box setting because it makes the diamond appear more round. But this is just a matter of personal taste. The compass can be applied to: - Four-prong settings Basket setting What’s in a name… The basket setting ring looks a lot like the original prong setting. Because just like in the classic design, the prongs extend from the base of the band and keep the diamond in place. But also, it has horizontal bands that connect and secure the prongs. Together they form a base for the diamond to lay in. We refer to this ensemble of lines as a basket setting or simply a wire basket. This kind of setting reduces the exposure of the diamond to knocks and bumps. Its higher durability makes this setting perfect for those with a busy lifestyle or work with their hands a lot. This setting covers the diamond a bit more. Therefore, the stone sparkles a little less compared to the classic design. The basket can be applied to: Four-prong settings Six-prong settings Compass settings Cathedral setting This setting features a band that rises to around the same level as the middle of the diamond. This way, it mimics the graceful arches of a gothic cathedral. The cathedral style makes the ring look more elegant. It highlights the (center) stone and adds a little height to the ring. We call cathedral settings also "tulip styled” settings sometimes. Because from the sides, the arches can look like a tulip as well. The cathedral settings lend themselves for several expansions. It is easy to add a halo or a diamond pave for example. The cathedral setting can be applied to: Prong settings Bezel settings Tension settings Bypass setting Last, but certainly not least. One of our favorite variations is the bypass setting. We also refer to it as the setting with a twist. Bypass rings have bands that overlap and part, rather than one continuous strap. The popularity of this type of solitaire ring setting dates all the way back to the Victorian era (around 1830). But to this day it is still a very beloved design. If you want to surprise your girl with a ‘classic with a twist’, a bypass ring is the way to go. Most of the time, we combine bypass settings with prong settings. However, they fit to practically every setting. One of the main downfalls of this setting though is that it is not stackable with other rings. The bypass setting can be applied to: Prong settings Bezel settings Tension settings Basket settings Is the perfect ring a combination of different elements? It’s hard to say which solitaire diamond engagement ring is the best one. All styles have their unique appearance and pros and cons. One last piece of advice I can give you is that all our ring settings are safe and keep your diamonds in place. Provided that you let a professional check them regularly. Hopefully, you now have a better idea of what you like and what you don’t like. Still, it can be tough to find that perfect ring; especially online. That is why our diamond consultants are standing by to provide you with personal advice. They help you to find the ring that meets all your requirements and – not entirely unimportant – your budget.

The diamond loupe

How to use a loupe to evaluate diamonds? To accurately view and evaluate a diamond, you first need to learn how to look properly through a magnifying glass. This trick is harder than it looks and goes as follows: - Hold the magnifying glass with your right or left hand as close as possible to one eye. - Keep both eyes open: with one eye closed, you aren’t able to see the depth of the diamond. Moreover, your eyes become less tired if you keep them both open. - Place your elbows firmly on the desk you’re working at. - Hold the loupe with your forefinger and thumb. With the little finger that is free, you can determine the distance to the diamond. - Move the diamond until you see it ‘crystal clear’. It may take some time before you get the hang of it, but eventually, persistence pays off. Once you’ve succeeded to look correctly through the loupe, you can evaluate the shape of the diamond, the color, and the purity. A loupe is also a very useful tool when you want to find out whether a diamond is real or fake. Different types of diamond loupes There are many different types of magnifiers that diamond workers use at their craft of cutting, polishing and grading diamonds. The ones that are most often used are: Linen loupe Gemstone loupe Table loupe Saw- or standing loupe Linen loupe or post stamp loupe The linen loupe is known by many names, including post stamp magnifier. This magnifying glass is often used by designers as CMYK color loupe. Advantages of the linen magnifier are that it lies well in the hand and is easy to use. The magnifier can simply be put on the table without damaging the glass or the desk. Gemstone loupe The gems magnifier, also known as a folding loupe, is often viewed as the standard diamond loupe. Especially in the trade of diamonds, this kind of magnifier is part of the standard equipment. This diamond loupe is small, handy and provides a detailed image of the diamond without biases in the cutting. The vast majority of diamond workers carry this kind of small magnifying glass in their pockets at all times. Standing loupe Probably less convenient than the gemstone loupe, but adequate for sure. The standing loupe (or ‘table loupe’) is particularly useful when the diamond worker needs to keep his hands free. If he needs to sort diamonds by color, for example, it might come in hand to use a standing magnifying glass. Saw loupe or tube loupe The saw loupes look a lot like the gemstone loupes. As with the classic diamond magnifier, the saw loupe looks also a bit like a small magnifying tube. Whereas other diamond loupes often magnify 10x or more, this one only magnifies 2 to 5 times. Magnifying more is not necessary for this loupe. This loupe is also used for diamond cutting, not just polishing. With a saw magnifier, you can look at the diamond at a safe distance from the saw blade without damaging the saw or the lens. What elements does a diamond loupe consist of? The lens of a diamond magnifier is made of optical glass or quartz glass, which is adapted to prevent achromatic discoloration. This can be done by grinding the glass in a certain way or using a combination of different lenses. This way you will always be able to see the true color of the diamond. The material in which the lens is put in must be solid, preferably metal. Metal is the strongest material, user-friendly and is durable. Regardless of the type of lens you use, metal is always preferred. Microscope for diamond evaluation Then there is the microscope. This is used to look for the smallest imperfections in the diamond and to review certain characteristics of the diamond. The microscope is not used for processing the diamond. A microscope is only used for the evaluation of diamonds that are already cut. With a microscope, you are able to look even deeper into the diamond to find even the smallest impurities and damages. For official and certified valuation of diamonds, a 10x magnification is the official standard. According to the official rules for diamond valuation, a microscope cannot be used to grade diamonds. However, due to the increased demand for perfection, microscopes are being used more and more often. Evaluating a diamond with a loupe yourself? The diamond rating takes a lot of work and looking through the loupe correctly is an art in itself. In our Diamond Masterclass, you learn to use the diamond magnifiers correctly and evaluate diamonds based on the 4 C's. You learn how to cut a diamond – which you can keep of course. The Masterclass is a must for anyone who wants to learn more about diamonds and who wants to sit on the cutting table themselves. Read more about the Diamond Masterclass at Royal Coster Diamonds.

The Journey from Diamond Mine to Diamond Ring

Diamond mine A diamond’s journey starts millions of years ago, kilometers deep under the surface of the earth. All over the world, there are diamond mines where mine workers try to find these precious gemstones. The mine in this photo is the Ekati mine, 300 kilometers northeast of Yellowknife, Canada. Rough diamond The most common shape for a rough diamond of gem quality is the octahedron. This looks like two pyramids back to back. Rough diamonds can be found in every shape imaginable, but the octahedron is the most common and most preferred one. Sawing and cleaving of the rough diamond The first step of transforming a rough diamond into a polished one, is the splitting of the diamond. The cutter must cleave it along the diamond's tetrahedral plane, where it is the weakest. He or she cutter places a steel blade in the groove and forcefully strikes it, cutting the rough diamond in two. Sometimes, diamonds have to be cut where there is no plane of weakness, which cannot be done with cleaving. Instead, the cutter saws the diamond using a phosphor-bronze blade rotating at about 15,000 rpm. Rough diamond after sawing or cleaving This is what a rough diamond looks like when it is split. During the cleaving or sawing, the cutter decides which parts of the diamond will become the table (the flat top of the stone with the greatest surface area) and the girdle (the outside rim of the diamond at the point of largest diameter). Then, he proceeds to polish. Determine how to polish When a diamond worker is polishing a diamond, he has to evaluate the diamond he is polishing frequently so he can take the 4 C’s into account. The diamond loupe is one of his best friends during this process. From two roughs to two brilliants The single rough diamond was transformed by the diamond polisher into two beautiful brilliant cuts. During its transformation from rough to polished, a brilliant loses about 50% of its size. This may seem like a lot but the sparkle you get in return makes definitely up for it. Popular diamond cuts A skilled diamond polisher can create every shape imaginable. The diamond cuts on the top row are – from left to right – Marquise, Pear, Emerald and Brilliant. The cuts on the bottom row are Cushion, Oval, Princess, and Heart shape. The round brilliant cut diamond is the most popular diamond shape. Our own patented Royal 201 The Royal 201 is a patented cut by Royal Coster Diamonds. It was created by our own Donny Griffioen and Bobby Low who were on a mission to create the most sparkling diamond the world would ever see. They found that the secret for the ultimate sparkle lies in the re-arrangement of crown facets and their angle. Including the amazing micro facetting of the girdle, the total facet count is 201. This is the ideal number of facets: the Royal 201. Many diamond experts consider this the most beautiful diamond cut in the world. Discover our most beautiful diamond pieces We worked hard to create a timeless classic collection of beautiful diamond jewelry. At the end of your tour here at Royal Coster, you have the opportunity to see these jewels for yourself. But first, let our guides take you on a tour through the magical world of diamonds and learn everything you ever wanted to know about diamonds and more here.