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Be careful of the prices of laboratory diamonds

Published on December 5, 2023

L'attrice Rosario Dawson con i gioielli Pandora Brilliance, con diamanti di laboratorio, lanciati nell'agosto 2022 in Usa e Canada

Why are the sales of artificial diamond jewelery created in the laboratory increasing? Those who love diamonds must take into account a trend that is becoming more and more popular: that of gems produced artificially, in laboratories. Research firm Brainy Insights recently estimated that the $10.8 billion lab-grown diamond market will reach $20.6 billion by 2032. Lab-grown diamonds are increasingly seen as a more attractive option. affordable compared to jewelry made with naturally mined diamonds. And more and more brands, from Pandora to De Beers, offer jewelery with laboratory-grown diamonds, now available in a wide range of sizes and shapes. And at an affordable price. So lab-grown diamond manufacturers are working with several jewelry companies and designers, particularly in Europe, to produce distinctive, fashionable and exclusive jewelry.

Bracciale tennis in oro bianco e diamanti di laboratorio — Tennis bracelet in white gold and laboratory diamonds by V Rai

Also according to the Bloomberg news agency, artificial stones, created in laboratories, are a growing market. Simply put, most artificial diamonds are made by two different methods: with carbon treated in a special microwave and strong overheating, which turns into a plasma ball, or strong compression is used. They are methods that simulate the natural process by which, over millions of years, diamonds were formed in the depths of the Earth. These processes (the two systems are called HPHT or CVD), however, require special machines (don’t try with your home microwave) to crystallize the carbon and transform it into gems also used (but not only) for jewellery. For this reason, in any case, defining laboratory diamonds as green is a stretch: the process of creating synthetic gems is still very energy-intensive. The largest producers of synthetic diamonds are located in India, China and the United States.

Synthesis diamond con taglio a pera — Synthesis diamond with pear cut, stone created in the laboratory

How do you recognize them?
Artificial diamonds are difficult to distinguish from natural ones. Only experts, with special machines and in laboratories with sophisticated equipment, can perceive the different characteristics, processing and cutting. Indeed, some synthetic diamonds have properties such as hardness, thermal conductivity and electron mobility that are superior to those of most natural diamonds. Impurities are generally avoided, but can be intentionally introduced to change some properties of the diamond. In short, distinguishing them is really difficult and, for a simple jeweler, almost impossible. This is also why natural diamonds are accompanied by a certificate that guarantees their authenticity.
Synthetic diamonds are usually very small, weighing less than 1 carat, although larger laboratory gems are starting to appear on the market. They are not just white, colorless. There are also fancy ones, in particular yellow and blue. The yellow comes from nitrogen impurities in the manufacturing process, while the blue comes from boron. Other colors, such as pink or green, are obtained using radioactive rain (but without danger to health, hopefully).

Anello in oro con diamanti di laboratorio della collezione Solstice — Gold ring with laboratory diamonds from the Solstice collection by Brilliant Earth

Do they cost more or less?
Synthetic diamonds are sold on average for 15-30% less than their natural equivalents. However, it also depends on their quality: even artificial diamonds are not all the same. According to the producers, the price should decrease further as production improves. Is it worth choosing them? But, be careful: Rapaport Group, which is a party to the dispute since it deals with information on the diamond trade, has raised an alarm with the aim of warning consumers about the retail prices of laboratory-grown diamonds, considered too high . According to Rapaport, some lab stones were purchased in bulk at prices up to 99% below list price for natural diamonds. But many retailers have not applied the same discount to consumers.

Anello in oro bianco con diamanti lab grown per 0,98 carati — White gold ring with lab grown diamonds totaling 0.98 carats

What is a cubic zirconia?

Published on October 12, 2022

Campus

Cubic zirconia: This stone is often used in jewelry. But few know what cubic zirconia really is. For example, what is a cubic zirconia made of? Is it very different from a diamond? What are the differences? The answers are known to (almost everyone) those who deal with jewelry. But, if you are reading this article, it is because you want to know exactly what are the characteristics of a cubic zirconia that, perhaps, is mounted on a ring or a pair of earrings that you are wearing.

Anello in metallo placcato con cubic zirconia by Stroili

Beware of the definition
Before explaining what a cubic zirconia really is, we need to clear up a misunderstanding. Often jewelry companies offer rings, necklaces, earrings or bracelets “with zircons”. Well, know that in 99.9% of cases it is not true. In fact, zircon is a rather rare and expensive natural stone (read also: Diamonds or cubic zirconia?). A cubic zirconia, on the other hand, is an artificial stone. So, be careful when you read that a piece of jewelry is composed of cubic zirconia, it is probably not true. Pay attention to it: those who use this marketing ploy propose fake “zircons” with metals such as steel or silver, hardly with 18-karat gold. By the way, sometimes cubic zirconia is denoted only by the abbreviation used in chemistry, CZ.

Anello in argento placcato oro e cubic zirconia — Anello in argento e cubic zirconia di PdPaola

What is a cubic zirconia?
In short, the answer is: it is (almost always) an artificial stone, produced in a factory. Although it looks like a diamond in appearance, a cubic zirconia is composed of zirconium dioxide and not carbon like natural gemstones. In fact, microscopic grains of natural cubic zirconia have been identified in nature: they are certainly not those commonly used in jewelry.

Orecchini a cerchio in argento e zirconia cubica colorata di Rosato

What is the difference with laboratory diamonds?
As we have explained, cubic zirconia is made up of zirconium dioxide. Man-made, lab-created diamonds are composed of carbon, like diamonds found in nature. To learn more, read also: What are laboratory diamonds?

Anello Champs Elysées in argento e cubic zirconia di Aliviero Martini 1A Classe

What are the characteristics of a cubic zirconia?
The main feature, which is the key to the success of cubic zirconia, is the resemblance to the diamond. But it doesn’t have the same properties. For example, if you look at the bottom surface of a diamond, you can see a rainbow reflection. Cubic zirconia, on the other hand, is limited to an orange and blue reflection due to a different refractive index. When exposed to short wave UV rays a cubic zirconia emits a fluorescence that tends to yellow, greenish yellow or beige. Another feature concerns the hardness. Cubic zirconia is at 8-8.5 on the Mohs scale, so it is a little harder than most natural semi-precious gems, although less than diamond, which is at 10. Yet cubic zirconia is considered brittle, yes breaks easily.

Anello a fascia placcato oro rosa con cubic zirconia di Bronzallure

How is cubic zirconia produced?
The most used method is the one called skull fusion. No one is beheaded: it is named for the shape of the crucible used which resembles a skull, surrounded by radio-frequency activated copper coils. It is a system patented by Josep F. Wenckus in 1997: it consists in heating the base material to temperatures of over 3000 degrees. With this method, however, it is difficult to predict the size of the crystals produced and the crystallization process cannot be controlled. To improve the result, several techniques have been introduced, including coating the finished cubic zirconia with a carbon film, similar to diamond, with a process that uses chemical vapor deposition. Or someone vacuum sprays an extremely thin layer of a precious metal (such as gold), which creates an iridescent effect. However, the effect is not lasting. The commercial production of cubic zirconia began in 1976. But it is not the only artificial stone to be used in place of diamonds. In fact, synthetic moissanite, with similar characteristics, has recently become widespread.

Collana in argento con cubic zirconia di Gerardo Sacco

How is it different from a diamond?
An expert gemologist can immediately discover the difference between a cobic zirconia and a diamond. For one thing, an artificial stone has no inclusions in it, as often happens with a natural gem. Furthermore, cubic zirconia weighs much more than diamond. It has a density that is approximately 1.7 times that of the natural gem. It is therefore sufficient to compare the weight of two stones of the same size. If you drop the stones in a liquid and compare the descent times you will see that the diamond will sink more slowly than a cubic zirconia, because it is lighter. The refractive index is also different: cubic zirconia has it of 2.15-2.18, compared to 2.42 of the natural gem. Paradoxically, moreover, cubic zirconia is more perfect than a diamond: only very rare natural gems are truly colorless (with a classification D). Most diamonds have a slight tinge of yellow or brown. A cubic zirconia is often completely colorless – equivalent to a diamond’s D. However, there is also colored cubic zirconia.

Anello in argento con zirconia cubica bianca di Pandora

What are baroque pearls

Published on December 30, 2021

Campus

Orecchini con fiori in legno di sawo intagliato e perle barocche indossati

What are baroque pearls? Here is a quick guide to baroque pearls and how to recognize the different shapes of irregular pearls ♦

Okay, they gave at you a necklace with baroque pearls. But do you know exactly what it means? No, they have not been fished in 1700 by someone who played the harpsichord. And, then, what kind of baroque pearls are? They are not all equal. Here’s everything you need to know about baroque pearlsì.

Anello con perla barocca di Thaiti e oro bianco, diamanti — Mizuki, anello con perla barocca di Thaiti e oro bianco, diamanti

Classical or baroque?

Classic pearls are perfectly spherical or almost, regular, smooth. These are the pearls that are used for classic jewels, such as the timeless necklace of regular-sized pearls or, more often, of increasing volume (the largest in front and the smallest towards the neck). Baroque pearls, on the other hand, are those that have a different shape from the simple one of the sphere. They don’t necessarily have to be asymmetrical or have irregular volumes. They are usually freshwater, while round and large pearls grow in salt water. In most cases, baroque pearls have an elongated sphere shape, are asymmetrical and do not have a smooth surface. This type of pearl was often used in Art Nouveau and Victorian jewelry, because romantically their shape resembles that of a tear. Baroque pearls are often cataloged with different names, related to their place of origin or their shape. Here are the most common names:

Spilla Bird in Heaven in oro bianco 18 carati, diamanti e perla barocca di Fei Liu

Coin pearls
They have a form that looks like a coin: round and a little ‘flat. They are very bright for their large surface area.
Twins pearls

They are single pearls that have fused together. Sometimes these Siamese pearls that are joined in a single element form a surprising volume, used to create out of the ordinary jewelry.

Delfina Delettrez, spilla coleottero con perla barocca

Cross pearls
Are a kind of coin pearls, which is combined to form a cross. They are flat as a coin pearl, but with waves and ridges.

Potato pearls
They are among the most common freshwater pearls: take their name from their irregular shape, but they are not elongated.

Biwa pearls
Are named after the place where they are located, the Lake Biwa, Japan. These pearls are pearls-stick calls generally flat, elongated, and shrink very much like a stick.

Egg pearls
They have an oval shape, with the bottom and top that shaking. These beads are punched along the large part, to the contrary.

Rice pearls
They are more like a classic pearl, but small, like grains of rice.

Heart pearls
They are flat and vaguely shaped like a heart.

Teardrop pearls
With the drop shape, they are similar to egg beads, but narrow and reminiscent of a drop.

Keshi pearls
They are the rarest type among the baroque pearls. They have a very uneven surface and a high gloss.

Gianmaria Buccellati 2001, spilla Panda con corpo formato da grande perla barocca , oro bianco, incassato in brillanti, con germoglio di bambù tra le zampe in oro giallo inciso. Diamanti fancy agli occhi — Gianmaria Buccellati 2001, spilla Panda con corpo formato da grande perla barocca , oro bianco, incassato in brillanti, con germoglio di bambù in oro giallo inciso. Diamanti fancy agli occhi

Yoko London, anello con perla barocca rosa e pavé di diamanti

Anello in oro rosa con perla barocca — Ornella Iannuzzi, anello in oro rosa con perla barocca

Perla barocca di acqua dolce con ametiste — Little H, perla barocca di acqua dolce con ametiste