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Royal Coster
Diamonds Size
MM / INCH (Circumference)
48 / 1.89 48 4½ 8
49 / 1.93 49 9
50 / 1.97 50 K 10
51 / 2.01 51 L 11
52 / 2.05 52 6 12
53 / 2.09 53 13
54 / 2.13 54 14
55 / 2.17 55 O 15
56 / 2.20 56 P 16
57 / 2.24 57 8 17
58 / 2.28 58 18
59 / 2.31 59 R 19
60 / 2.36 60 9 S 20

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7 common mistakes when buying a diamond - Royal Coster Diamonds

7 common mistakes when buying a diamond

1. "A diamond doesn’t need a certificate"

Each (real) diamond has its own certificate provided by the GIA. GIA is the "Gemological Institute of America" and is the organization that judges diamonds. By studying the GIA certificates, you can see that not all diamonds are the same. Diamonds can differ in carat, color, clarity, and cut. The differences between these four characteristics (also known as the 4 C's) determine the price of the diamond. iamond certificate with loose diamond It can be difficult to evaluate a diamond with the naked eye. For example, two similar diamonds may differ in purity, even though you do not necessarily see this. The grinding quality is also difficult to judge without specific diamond knowledge. Every polished diamond shines, but the most beautiful glitter is only achieved when all facets are on the right degrees and the proportions are perfect. Two equal diamonds can give a different glimmer under the same conditions. Therefore, always check the certificates of the diamonds before you make a purchase.

2. "There’s nowhere specified that this is a blood diamond, so it must be alright"

This is a very dangerous assumption. In addition to everything that is in the certificate, there are some diamond features that aren’t on there. One of those things is the origin of the diamond. There are a few areas where you really don’t want your diamond to come from. The so-called blood diamonds or "conflict diamonds" come from conflict areas. With the sale of blood diamonds, corrupt governments are maintained as is the sale of weapons to create conflicts. woman holding ring in sorrow For honest people who do not want anything to do with it, a certification process has been set up for fair diamonds. In the so-called 'Kimberly process', it says that every invoice of purchased rough diamonds needs to be provided with a signature. That signature is proof that the sold diamonds do not come from conflict areas. At Royal Coster Diamonds we do not sell blood diamonds. With us, you are therefore sure your diamond was obtained in a fair and safe way so you can wear it carefree.

3. "It doesn’t matter which diamond lab rated my diamond"

Strangely enough, every gemstone laboratory can set its own standard for grading diamonds. One laboratory can therefore rank a diamond a lot purer than another lab. Some dealers and retailers prefer to do business with a laboratory that sometimes judges the stones 3 to 5 degrees higher. This will increase the margins for the seller. He sells the diamond for more money than it's actually worth. As a buyer, however, you cannot check this and just pay too much for a less pure diamond. man evaluating diamond in diamond lab This is of course not a fair trade. Fortunately, there are also laboratories that do play by the rules and are certified and qualified. If your diamond has a certificate from the agencies IGI, GIA or HRD of Antwerp, you know your diamond is rated properly. These agencies use the true value of diamonds.

4. "If I negotiate well, I get the price down a lot"

We understand that it seems attractive to hope for the finest quality for the lowest price. Diamonds as big as possible for as little money as possible. Just remember that the prices of diamonds with a valid certificate, with the gradient that you want, have usually fair and fixed prices. These are determined by the umbrella organization of diamond dealers. Want a lower price? Then you will have to hand in on quality. man and woman shaking hands All certified diamonds are worth their price and bargains almost never occur. If something seems too good to be true, it is usually not true either. You can hear pretty stories of cheap diamonds. However, when you look closely at these diamonds later, you're brought down to earth with a shock. Often there is something wrong with the clarity, color, cut or carat of the diamond. If you're totally unlucky, it's not even a real diamond! Buy a diamond that you like yourself. A diamond goes on for generations and is a good investment because a diamond retains its value. Therefore, you can better take one you really like.

5. "All diamonds are perfectly cut"

Diamond is a natural product and the craft of cutting it is done by hand. Sometimes a cutter has to use all his craftsmanship to perfectly grind a gem. For example, a cutter may choose to deliberately deviate from the standard to get a diamond in perfect condition. Sometimes he will encounter a bad spot in the stone. two loose diamonds on fingers A good polisher does everything to cut away this so-called pique. If that’s not possible, he grinds the diamond in such a way that the inclusion ends up in another place. He puts the pique in such a way that it affects as little of the diamond's brilliance as possible. It is therefore important that a beautiful diamond is cut by a good grinder since a bad cutter could mess up the diamond’s sparkle.

6. "There is a certificate, so it will be all alright"

If you want to buy a large and high-quality diamond, do it at a good and reliable supplier. Here you are sure that you get the correct certificate with your diamond. Make sure that all diamonds on your purchased jewelers are of the same quality. This quality should also be stated on the certificate you receive. iamond between tweezers above certificate If your new piece of jewelry consists of different types of diamonds, then all types are mentioned separately on the certificate. Also, dive into the reputation of the jeweler. The better its name, the surer you are that the value of the diamonds is good. Check reviews, the website and social media of the company and read the comments. This is a quick way to find out whether the jeweler is reliable.

7. “Diamonds are much cheaper in foreign countries”

There are many stories about places where diamonds would appear to be a lot cheaper than in regular stores. Examples of this are:
  • - A big jewelry fair
  • - A large diamond sale
  • - Abroad or during a cruise
  • - Only online stores
road sign myth fact

Myth 1: diamonds are cheaper at a big jewelry fair

At large exchanges, high-quality stones are rarely sold. This is because fairs often have to pay high prices for stands. Also, travel expenses and associated insurances are always high and are calculated by the seller in the diamond price. You can imagine who is going to pay for these extra costs…

Myth 2: score cheap diamonds on sale

Diamonds - and jewelry in general - don’t have “factory prices” as opposed to, for example, clothing. As explained at #4, fair diamonds have a fair price. Statements such as “Sale” and “50% discount” should be taken with a grain of salt when it comes to diamonds. Whoever falls for these kinds of promises will often come out deceived.

Myth 3: diamonds are cheaper abroad

Rough diamonds have a fixed price in dollars all over the world. They are therefore not cheaper in one or another country. There are many stories on the internet of people who were tempted to buy a diamond abroad. Back home, they discovered they fell victim to a scam artist. In some cases, the diamonds are not even real and the metals are of poor quality. The only way to sell diamonds cheaper is to lower the costs. A good diamond cutter receives a good salary, just like everyone else who does their job well. A moderate diamond cutter deserves a moderate wage but also delivers moderate quality. In addition, the seller can save on the materials the diamond is put into. Silver is cheaper than gold and 9-carat gold is less expensive than 18-carat gold. Still, it seems like a waste to put a beautiful diamond in a cheap metal. Therefore it is extra important you make absolutely sure the diamond you buy is real when it’s in a cheaper material. Of course, you can buy jewelry abroad for a small amount of money as a souvenir. However, don’t spend thousands of euros on something you’re not sure whether it’s real. man looking sceptic at diamond jewelry store

Myth 4: diamond sellers without a physical store are cheaper

You don’t have to wander through the internet long to find companies selling diamonds online. Assuming they are fair businesses, they will never really be much cheaper than regular companies. Even though they may act as if they are cheaper, they still have to deal with the fixed prices. Every company has their costs: whether it’s a jeweler, goldsmith or online store. The one has higher staff costs and the other has higher insurance costs for example. This is the best case scenario. Online there are many bad diamond sellers. If you buy a diamond there, you can never check whether the attached certificate belongs in fact to that particular diamond. In addition, small jewelers and online stores will never have a huge supply of precious diamonds. Most sellers simply can't afford this because the conversion rate of diamonds is fairly low in most cases. At Royal Coster however, we have more than 40,000 loose diamonds in stock. We have diamonds in all different qualities and sizes so everyone will find exactly what they are looking for. Partly this is because we cut the diamonds ourselves, but we also need a large stock because we do have a high turnover rate.

The guarantees of Royal Coster Diamonds

With us, you’re sure to get fair diamonds at a fair price. At Royal Coster Diamonds, you’re sure to get diamonds for the best price possible. This is because we get diamonds directly from the source without an intermediary. In addition, we also have the largest collection of diamonds and diamond jewelry in stock in the Netherlands. Visit our store in Amsterdam or book a free diamond tour to see how our diamonds are cut.
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