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Short guide to diamonds

Published on April 14, 2024

Diamante ovale impeccabile D Color da 102,39 carati

Do you know how to distinguish diamonds? What are the four Cs? How are the diamonds evaluated? Here is a quick guide to solve any doubts about diamonds ♦

Diamonds are the most precious stones. But how much are the diamonds of a ring, earrings or necklace really worth? They are all the same? How to recognize and judge them? Gioiellis.com helps you with this exclusive guide, which you can print and save. With a premise: understanding does not mean being able to make an assessment yourself. For a safe and definitive evaluation of a diamond it is better to contact an expert who can view the stone directly.

The Rock, diamante a forma di pera da 228,31 carati — The Rock, 228.31 carat pear-shaped diamond

WHAT IS A DIAMOND?
The substance is one of the many forms in which carbon can occur. In scientific terms, the diamond is constituted by a crystalline lattice of carbon atoms arranged according to an octahedral structure. The name derives from the ancient Greek ἀδάμας, that is, adámas, which means indestructible, just or even immutable.
Diamonds are the deepest material of our planet that has ever reached the earth’s surface and are considered an open window inside the Earth. A material that can not be obtained by any other means. Far beyond their economic value, they have a higher scientific value, because they are able to tell many things about the evolution of the Earth.

THE ORIGIN
The existing diamonds for 94% were formed between 1 and 3 billion years ago at depths between 150 and 200 kilometers, where the very pure carbon, subjected to enormous pressure, generated these stones of great charm. The remaining 6% of diamonds is even more interesting and originates in the “transition zone of the Earth”, between 660 and 2,900 kilometers of depth. They are called super-deep diamonds.

Medaglione Ellesmere, composto da 478 diamanti — Ellesmere medallion, composed of 478 diamonds by De Beers

FEATURES
The diamond is the prince of jewels thanks to the dispersion of white light in the colors of the spectrum, one of its main characteristics. The hardness of the diamond is its other peculiarity, which makes it useful for many industrial applications. Today the global production of rough diamonds is estimated at around 130 million carats (26 tons) per year, of which 92% is cut and polished in India, mostly in the city of Surat. After the first processing, about 85% of rough diamonds, 50% of cut diamonds, and 40% of those for industry are traded on the market in Antwerp, Belgium. The reason is that in the late Quattrocento in Antwerp a new technique was introduced to polish and give shape to the gems. There are more than 12 thousand cutters and polishers at work in the diamond district.

SHORT HISTORY
Diamonds have been known for hundreds of years and have been used as decorative elements since ancient times: the first references have been registered in India. Today the most common use of diamond in jewelry is for the engagement ring, but few know that it is a fairly recent convention, which became popular in the first half of the twentieth century thanks to an advertising campaign by De Beers, the company leader in the diamond trade. More generally, however, diamond rings have been used at least since the fifteenth century to symbolize a commitment.

Anello Dôme di Buccellati, con diamante taglio smeraldo — Dôme ring by Buccellati, with emerald-cut diamond

THE EVALUATION
Diamonds are not all the same. To evaluate them they are classified according to four «C», taking into account the English language: carat (carat), cut (cut), color (color) and clarity. But there are also other characteristics: for example, the presence or absence of fluorescence, which can influence the choice in use for a piece of jewelry and value.

CARAT
Carat weight measures the mass of a diamond. One carat is 200 milligrams. The price per carat increases with weight, since the larger diamonds are rarer and more in demand as precious stones. In contrast, the value does not increase linearly in the same way with the dimension. For example, a diamond of 0.99 carats can have a much lower price (always per carat) than a 1.01 carat analogue: the difference is caused by the difference in demand.

I gradi di trasparenza del diamante — The degrees of transparency of the diamond

CLARITY
Clarity measures the internal defects of a diamond, called inclusions. Inclusions may consist of crystals of a foreign material, or structural imperfections, such as small cracks or, finally, as a whitish halo. The number, size, color, relative position, orientation and visibility of inclusions can affect the relative clarity of a diamond. The Gemological Institute of America (Gia) and other organizations have developed systems to define the degree of clarity, starting from inclusions that are visible to a professional with a diamond observed at ten magnifications. Only about 20% of all the diamonds extracted have a sufficiently high clarity score for use in jewelry. The other 80% is relegated to industrial use. Of that first 20%, a significant share contains one or more visible inclusions. Stones that do not have a visible inclusion are known as “eye-clean”, clean to the eye, and are obviously the favorite pieces. Attention, sometimes inclusions are hidden under the frame of a piece of jewelry: to find out, you should deconstruct the jewel to examine it. Most of the inclusions present in a diamond, in any case, do not affect the structural integrity of the gem. However, the so-called “clouds” of large dimensions can affect the ability of a diamond to transmit and diffuse light. And large cracks near the surface increase the possibility of a fracture.

Le sfumature del diamante — The nuances of the diamond

COLOR
What is the best color for a diamond? Simple: what is not there. In fact, the most precious variety of diamonds is totally colorless. Also in this case there is a classification, which should be certified by those who sell the jewel: the totally colorless diamond, therefore of the best quality, is classified as D. The next grade, certified with the letter E, has an almost invisible trace of color , which can only be observed by experts in a classification laboratory. The scale continues: even the F diamonds are almost transparent. The stones that, instead, show very small traces of color are classified as G or H. Again: the slightly colored ones are classified as I or J K and up to Z, with a bright yellow coloring. The latter, even if they are at the end of the scale, are however quite rare and therefore very appreciated. Diamonds with unusual coloring are sometimes labeled as fancy (fantasy). Some, like the pink ones, are very rare. The color of a diamond can be caused by chemical impurities and / or structural defects in the crystal lattice. Depending on the shade and the intensity, the color of a diamond can diminish or increase its value. For example, intense blue diamonds (like the one baptized by Hope) are remarkably precious. However, these are exceptional pieces. Most diamonds used as gems are fundamentally transparent, with a small tinge, or white diamonds. The most common impurity, nitrogen, replaces a small percentage of carbon atoms in the diamond structure and causes a yellowish or brownish color.

I tipi di taglio del diamante — Some diamond cuts

CUT
The cut of a diamond describes the way in which a diamond was formed and refined by its rough stone shape. In fact, it describes the processing quality and the angles to which it is cut and is often confused with the concept of form. The cut is not accidental: there are mathematical guidelines for determining angles and length ratios in order to reflect the maximum amount of light. The techniques for cutting diamonds have developed over hundreds of years. But the best results were obtained in 1919 by the mathematician and passionate of gems Marcel Tolkowsky: it is he who developed the brilliant, round cut, calculating the ideal shape to diffuse the light. The brilliant has 57 faces (polished), of which 33 on the crown (the upper part) and 24 on the pavilion (the lower half). The belt is the thin central part. The function of the crown is to refract light in the colors of the iris, while the function of the pavilion is to reflect light through the top of the diamond. The culet is instead the smallest surface in the lower part of the diamond: it should be of a negligible diameter, to avoid the loss of light from the bottom.

Il diamante battuto da Sotheby's per 13,8 milioni di dollari — Oval diamond sold at Sotheby’s for 13.8 million dollars

VALUE
If you want to be updated on the market price of diamonds you can follow the Rapaport Diamond Report (in English), which is published every week by Martin Rapaport, CEO of the Rapaport Group, in New York: it is considered the de facto reference point of the retail price. In the wholesale diamond trade, the term carats is often used to define a sale or purchase. For example, a buyer can place an order for 100 carats (20 g) of 0.5 carats (100 mg), with certain characteristics. In this case the Total carat weight (T.c.w.), ie the total carat weight is used to describe the total mass of diamonds or precious stones in a piece of jewelry. The “solitaire” diamonds for earrings, for example, are usually expressed in Tcw, indicating the mass of diamonds in both earrings and not of every single diamond. Tcw is also widely used for diamond necklaces, bracelets and other jewelry. A quick indication: look at the overall diameter. Typically a 1.0 carat round brilliant (200 mg) should have a diameter of about 6.5 mm. Mathematically, the diameter in millimeters of a round brilliant should correspond to about 6.5 times the cubic root of carat weight, of 11.1 times the cubic root of weight grams, or 1.4 times the cubic root of weight point. In short, to evaluate the true value it takes very precise instruments and a good eye.

Modella con collana composta da 374 diamanti bianchi e gialli — Graff, model with a necklace made up of 374 white and yellow diamonds

Expert advice for buying diamonds

Published on March 31, 2024

Campus

Diamonds, rubies, emeralds, sapphires: which is their value? How to recognize them? Some people buy them to make up for something, someone to love, for others is a safe haven investment. Whatever the motivation, the opinion of an expert is crucial. Mainly because when it comes to diamonds, there are parameters which are a kind of list of basis for the listing, but for colored gemstones such as emeralds, rubies and sapphires the matter is not simple. What to be careful and what criteria adopted for the selection, is explained by Pio Visconti, Italian Gemological Institute lecturer, consultant of many regional entity and owner of the Gemological Centre based in Valenza. The proof that it is a famous gemologist, lies in the fact that his skill is cited as a guarantee in the auction catalogs, in case of its certification of the jewel. «How to evaluate a stone? If you were to buy a Rolex goes from the authorized dealer or call for a friend who bought it on the subway?», says in this interview with Gioiellis.com .

Pio Visconti in tenuta da golf — Pio Visconti in golf attire

Question. Which among the famous four C carat, color, clarity and cut, it is more important when choosing a diamond?Answer. The criterion that must prevail, in my opinion, is cut. Of course weight, color and clarity are important, but because spending a stone IF 40 points and 70 points maybe a Vs2 is quite similar, the fact remains that when the diamond is set must shine on the frame, it must be a mountain of light, as the ancients said, and this can only be achieved with a good cut.

Fedi eternity in diamanti — Eternity wedding rings in diamonds

Q. But those who are not in the industry how can recognize a good job? They only rely on their aesthetic sense?

A. In the certificate are visible the numbers that refer to the values of the upper part, for example 57 %, and the height of the crown 14%. To the customer does not say anything and that is why beside is written the analyst’s judgment: excellent, good, average, as proportions or as accuracy. Ultimately, I’d recommend a diamond cut-out great, because the other criteria are linked to the price.

Q. What do you do if the certificate does not exist?

A. I do have a question: if you were to buy a Rolex goes from authorized dealer or call for a friend who bought it on the subway?

Anello Legends of Africa con diamanti bianchi e smeraldi — Legends of Africa ring with white diamonds and emeralds

Q. Many well-known brands are keen to highlight the exclusive use of certified diamonds, but there is the risk of receiving the certificate of another gem?

A. Anything can happen, but ruining his reputation for a non-transparent behavior for little gems of value is not worth it, especially since it takes very little to turn into a business catastrophe. In cases of very rare stones, the diamond is sealed with his certificate inside, even in the last decade is increasingly the request of engraving the certificate number on the girdle of the stone itself.

Q. The race to the certification also depends on the remarkable technological developments in producing synthetic diamonds that are derived from carbon yes, but made in a laboratory, and on the increasing of the number of natural stones modified by man to make them look more beautiful. The Gemological Institute of America (Gia), has even developed a 3D software to mask false. Does it work?

A. It is one more tool, but alone is not enough. The job of the gemologist is to identify the authenticity of the stone with a suitable instrumentation. In addition, there is a price list of the maximum for each of the 4 C, but the precise value is determined by supply and demand. Traders can even evaluate the stone without even seeing her, precisely because the certificate is authentic. Things however, is terribly complicated with colored stones: no certifying agency in the world is able to identify parameters in a serious manner that may suggest the value of an emerald, a ruby and a sapphire. And for precious stones is even worse.

Esame di un diamante a un precedente Dubai Jewellery Show — Examination of a diamond jewel

Q. It is said that the origin of the gems will determine the quality. It is true that the Burmese rubies are the most beautiful, as well as Colombian emeralds need to be?

A. It is a simplification: it is known that a Burmese ruby usually has the characteristics of exceptional color because it is bright red, shiny, without saturation of dark tone or purple, almost the shade of the Ferrari cars to be understood. This does not mean that similar stones can not be found even in deposits of other countries, but they are certainly rarer. For example, those thai have excellent transparency, but also a purplish tinge, or a very small saturation blue. The same applies to emeralds: some exemplar, magnificent for color and transparency, the typical characteristics of beryl Colombians, were discovered in Brazil. Sapphires of Kasmhir are of a incomparable blue, but rare, while those of Ceylon are lighter but warmer tinge and, yet, those of Siam are of a very intense shade.

D. If the origin does not guarantee the quality, what about the cut?

A. The colored stones have most complicated crystal systems than diamonds, what matters is a good symmetry and uniformity color view from above, because you will never get this profile. For this reason, a cut not perfectly centered is acceptable in emeralds, rubies and sapphires. On the contrary, it is unacceptable in a diamond.

Q. And it always comes back to cutting …

A. Make the most of both the weight and the color of the gem depends on the skill of the cutter: Australian sapphires are very dark with a greenish overtones and therefore unloved, they are usually sliced thin enough to avoid accentuating the gloom. Instead, those from Ceylon with very nice shades, but not so intense, have a much larger pavilion to enhance the color.

Rubino birmano color sangue di piccione non riscaldato da 6,41 carati, montato su un anello in oro giallo e bianco di 18 carati, circondato da diamanti, progettato da Forms — 6.41 carat unheated pigeon’s blood Burmese ruby set in an 18k yellow and white gold ring surrounded by diamonds, designed by Forms

Q. But then the criterion of choice for these stones is the color?

A. Yes, it must be as pure as possible, reflect the idea of green or red or blue we have. Obviously, I do not see inclusions with the naked eye, maybe you can help me with a diopter glasses or two, because imperfections will lower the value. And if you happen to want to do some shopping while traveling, before you buy a stone better go before a certifying agency of the place.

Anello Margot con zaffiro taglio pera e diamanti — Margot ring with pear-cut sapphire and diamonds

Q. What are the most common counterfeits and the most economically harmful? We often hear about emeralds “No Oil ” as a sign of authenticity. Is also true for rubies and sapphires?

A. Of all the treatments mentioned is that most harmless and also the oldest: Plinius mentions in his writings that make for the most beautiful emeralds was enough to soak them in the oil. The micro-fractures resin impregnated: yes those who are serious. For sapphires the most resounding method is thermo-diffusion, which tinged with blue a natural corundum completely colorless and reduces the value one-tenth. The outcome? A gem from 70 euro including treatment, may also be assessed 1,200 Euros. While the roots of ruby, so named because opaque, are rubies of very low quality, that with a very sophisticated technique, receive infiltration glass. Are generally lead to increase the effect, in order to make the rubies completely transparent. So, a 4 -carat stone of the cost to trade effortlessly exceed 100 dollars, has the same appearance of one evaluated a 5 thousand dollars.

Q. So the certification agency guarantees the authenticity and origin of the product?

A. Yes, it checks whether it is natural or synthetic , in the first case, it has undergone treatment. Thanks to the inclusions, which are the traces of the rock in which the rock was formed, it is possible to trace the geographical area. Value there is a very wide gap related to trade, fashion, personal perception.

Pietre di colore: zaffiro, rubino, rubellite e zaffiro giallo — Color stones: sapphire, ruby, rubellite and yellow sapphire

What are carats?

Published on August 9, 2023

Campus

How many carats is your diamond in? And how many karats is your gold ring instead? For those who are not a jewelry expert or do not know the basic rules of the world of jewelry, the carats are a big mess. The carats that are the unit of measurement needed for precious stones and pearls, in fact, are a completely different thing from the karats that refer to gold. Did you know? In English, everything is easier: the carats that measure diamonds start with the letter C while those for gold start with the K. In other languages, however, it is written the same way and everything is more complicated.

This is why we must be careful not to confuse the different concepts: the carats of diamonds (or rubies, emeralds, sapphires, etc.) with the karats that are related to gold. Here’s how to distinguish.

Diamante a cuore di Recarlo — Diamond in the heart of Recarlo

The carats of the stones

The carat (the abbreviation is ct) is a unit that indicates the mass of a stone or pearl. Carats are used for convenience, after in past each country regulated itself differently for centuries. For those who traded in diamonds or other stones it was therefore difficult to work. In Florence, for example, the basic unit of measurement was equivalent to 197.2 milligrams, while in London to 205.49. After much discussion, in the end, in 1907 it was decided to adopt 200 milligrams as a carat measure. A single carat, therefore, equals one fifth of 1 gram.

Anello con diamante bianco ovale da 31,82 carati — 31.82 carat oval white diamond ring

Now you know exactly how much the diamond on your finger weighs: divide the number of carats by five and you will have the weight in grams. Or, more easily, in milligrams, since it is not common to wear a diamond that weighs 5 carats (and therefore 1 gram). for this reason the carat is divisible into 100 points of 2 milligrams.

Anello di Van Cleef & Arpels a forma bombata con diamanti — Van Cleef & Arpels rounded shape ring with diamonds

By the way, why is the carat called so? The origin seems to be linked to carob seeds. The word carat derives from the Arabic qīrāṭ قيراط, which however is derived from the Greek kerátion κεράτιον, which indicates carob seeds. And these seeds were used to weigh jewels, thanks to their always regular shape. Then the term carat was used in Italy and later in the rest of the world. The use of the carat unit of measurement to weigh diamonds dates back to 1570.

Selezione dei diamanti nel laboratorio di Antwerp (Anversa) — Selection of diamonds in the Tiffany laboratory in Antwerp

The karats of gold

The carats of diamonds, precious stones and pearls refer to weight. The karats of gold, on the other hand, indicate the percentage of yellow metal present in a jewel, its fineness. The term karat has prevailed among the many systems adopted in the past and, in particular, on the measurement of pounds and ounces, which are still used for the weight of gold, platinum or silver. So why this confusion? Simple: the ancient origin of the word is the same, i.e. the carats used to measure precious materials.

Anello a fascia in oro 22 carati — Band ring in 22 carat gold

In the case of the karats that refer to gold, however, they indicate the thousandths of quantities of gold (or other precious metals) contained in an alloy. The maximum, as regards gold, is 24 karats. You will never find gold of 25 or more carats. The 24 karats indicate that the gold is 100% pure. The 24 karats are the basis for calculating the rest (always for gold). The 18-karat jewels, therefore, are 75% gold. It is calculated as follows: 18: 24 = 0.75. Similarly, a jewel with 14% gold means that it contains slightly more than half of gold, the rest are other metals (14: 24 = 0.58).

In some cases, the karats of gold can also be indicated with the number that refers to the percentage (the result of the arithmetic division). For example, 18-karat gold can also be indicated with the initials 750, 14-karat gold with 583 and so on. Again, if you read the number 375 in a jewel, know that it equals 9 karats.

The karats are also used for silver. The silver sterling, for example, contains 92.5% of silver and 7.5% of other metals, generally copper. It is generally referred to as 925 silver.

Anello Wave Stacking in oro 24 carati — Menē, Wave Stacking ring in 24 carat gold

Anello Bahia in oro 18 carati e diamanti — Bahia ring in 18K gold and diamonds

Anello in oro rosa 14 carati — 14K rose gold ring

Anello in oro rosa 9 carati e diamante ice — Ring in 9 carat rose gold and ice diamond

Anello in argento satinato e lucido — Satin and polished 925 silver ring

How to recognize if a jewel is gold

Published on March 24, 2023

Campus

Gioielli della collezione Legàmi di Lenti & Villasco indossati

Raise your hand if you don’t have at least one gold jewel. A ring, a pair of earrings, a gold necklace or bracelet are perhaps the most common gift that is reserved for anniversaries or special occasions. But are you sure that the jewel is real gold? There are several ways to recognize if a jewel is made of real gold.

Orecchini e collana in oro — Gold earrings and necklace

1. Check the carat indication
Gold jewelry is often marked with hallmarks that indicate the purity of the gold. The most common hallmarks are 14K, 18K and 24K, or Ct for an Italian jewel. K or Ct denotes carats, the measure of gold purity. 24K gold is pure gold, while 14K gold is 58.3% gold and 18K gold is 75% gold. The hallmark should be in another inconspicuous location. If you want to know more about gold karats read here.

Questo anello in oro della francese Marie Mas indica l'oro 18 carati con il numero 750 — This gold ring from the French Marie Mas indicates 18k gold with the number 750

2. The magnet test
Gold is not magnetic. So if a piece of jewelry is attracted to a magnet, it’s not made of real gold. However, keep in mind that other metals, such as stainless steel or silver, are also non-magnetic, so this test alone isn’t always reliable. But it is still an attempt that can be made.

Collana e orecchini Lunaria Alta indossati — Worn Lunaria Alta necklace and earrings by Marco Bicego

3. The nitric acid test
This test can determine the purity of gold. A small hidden scratch is made on the jewelry and a drop of nitric acid is placed on the mark. The color of the scratch after the acid has been applied will indicate the purity of the gold. However, this test can damage your jewelry, so it should only be done by a trained professional.

Anelli della collezione Anime indossati — Rings from Leonori’s Anime collection worn

4. The density test
Gold is a dense metal, so it will weigh more than most other metals of the same size. A jeweler can perform a density test by measuring the weight of the jewel and calculating its density. However, this test requires specialized equipment, so it may not be within your reach.

Collana Ivy in oro rosa e diamanti indossata — Ivy necklace in rose gold and diamonds by Nanis worn

5. The skin test
Genuine Gold Does Not Cause Skin Reactions or Discoloration: If you wear your jewelery and observe skin reactions it is likely that the jewelery is not made from genuine gold. However, keep in mind that some people may have allergic reactions to other metals, such as nickel, which may be present in gold jewellery, especially older ones.

Collezione Crescendo di FerrariFirenze, gioielli indossati — Crescendo collection by FerrariFirenze, worn jewels

In summary, to recognize if a piece of jewelry is made of real gold, you can check for hallmarks, do a magnet test, do a nitric acid test, do a density test, or do a skin test. However, some of these tests may require specialized equipment or skills, so it is best to have them performed by a trained professional.

Dune-Velaa-pave_bracciale-indossato — Dune Velaa Pavé by Annamaria Cammilli, gold bracelet worn

A white gold ring?

Published on April 25, 2022

Campus/Rings

Anello in oro bianco e diamante della linea Anniversary Love by Recarlo

White gold is the metal you like best, especially those who get married. But do you really know everything about white gold? Maybe you think of buying a ring? This metal, in fact, has strengths, but also some flaws: better to know everything first. In this article, we explain the characteristics and weaknesses of white gold.

Il classico anello in oro bianco e tre diamanti di Tiffany & co.

According to the American marketing company GemFind, in fact, the most searched metal on the web in 2019 was 14 carat white gold, with 41% of clicks, followed by 18 carat white gold with 11%. In short, over half of the research concerns precisely white gold: a sign that it is the preferred metal, certainly in the USA and in Europe.

Anello in oro bianco — Bluespirit, anello in oro bianco

Why gold turns white
Gold in nature is yellow. White gold, in fact, is obtained by mixing the original yellow metal with other elements to lighten the color. The most common alloy for making gold white includes nickel, palladium, platinum and manganese. But sometimes copper, zinc or silver are also used, but these metals have contraindications because they can oxidize on contact with air and skin. Alternatively, a thin platinum plating (which is naturally white) in alloy with iridium, ruthenium or cobalt can be used, which add strength to this alloy.

Anello ondulato in oro bianco e diamanti — Orsini, anello ondulato in oro bianco e diamanti

How much yellow gold is there in white gold?
It depends on the carats, a measure that serves to indicate the proportion between the yellow gold contained and the other metals. 18-karat white gold is composed of 75% original metal and 25% other metals. 14-karat gold has only 58.3% of natural gold and for 9-karat white gold the proportion is reduced to 37.5%.

Anello in oro bianco e diamante taglio marquise — C&C, anello in oro bianco e diamante taglio marquise

The right color for white
Many buy a white gold ring because it has a very simple color and is shiny on one finger, perhaps because there is also a beautiful diamond in addition to metal. But white gold isn’t actually polished. Indeed, it is opaque. The glossy white, in fact, is obtained with the rhodium-plated metal plating, a patina is applied to all the white gold jewels. Without rhodium plating, white gold may appear gray, tending to beige or pale pink.

Nickel allergies
Warning: white gold, especially in the past, has often been obtained with the massive use of nickel, which corrects the yellowish white tinge. But nickel is also a metal that can cause allergies: about one in eight women suffers from it. Those who suffer from nickel allergies must make sure that the white gold that contains nickel has been rhodium: the external patina, in fact, avoids the contact of nickel with the skin.

Anello in oro bianco e diamanti della collezione Milano di Pomellato

Plating
As we have mentioned, white gold jewelry usually has a platinum or rhodium plating. Plating makes the jewelry sparkly, but it also has two weaknesses. The first is that plating prevents a ring from being easily tightened or enlarged. Because, of course, rhodium plating must be done again. The second problem is that this patina fades over time and must be applied again. Rhodium plating can also be lost due to sweat from the skin or frequent contact with detergents, other metals or commonly used items. Therefore, if you wear the ring often, the rhodium plating should be done every two years or so. If you do not do the rhodium plating again, the ring will begin to have a yellow and opaque hue. But don’t be afraid, it’s an operation that lasts a couple of hours and is not too expensive.

Qayten, anello Origami in oro bianco e pavé di diamanti

What is the difference between yellow gold and white gold?

Published on October 12, 2021

Campus

What is the difference between yellow gold and white gold? Obviously, the color. But you want to know more. It’s a good idea, because there are a lot of differences between yellow gold and white gold. And even the valuation, in case you want to sell a jewel, can vary, both for yellow gold and for white gold. So, besides the color, what are the differences between yellow gold and white gold? And does white gold cause allergies?

Anello chevalier in oro bianco — Schreiber white gold chevalier ring

Let’s start with a fact: the gold that is extracted in the mines or in the straws found in the sand of some rivers is yellow. In nature there is no white gold, which is a human invention. White gold is produced by combining yellow gold with other metals. But, let’s open a parenthesis: almost all yellow gold jewels are also alloyed with other elements. Gold in nature is 24 carat, but it is also very malleable. 24-karat gold jewelry is easily deformed and is used only by very few jewelers, especially in countries such as India. In general, however, gold is used for jewelry that is melted with other metals, such as copper or silver, which make it more solid.

Spilla in oro giallo e bianco con diamanti e perla barocca al centro — Brooch in yellow and white gold with diamonds and baroque pearl in the center by Buccellati

How much pure gold is there in a jewel? The answer is easy: the carats indicate it. For example, an 18-karat gold ring will have 750 parts of pure gold and 250 parts of other metals. Or, a jewelry with 14 karat gold will have 585 parts of gold and 415 parts of other metals. And with 9 carats the percentage of pure gold drops to 375 parts or, if you prefer, it is 37.5%. Of course, with less carats of gold the value will also be lower.

Anello in in oro 24 carati martellato — Hammered 24 carat gold ring

And what about white gold? The same concept applies to white gold as well. But, unlike yellow gold, it is melted together with white metals, to form an alloy that makes it lose all or almost the yellow color. In short, it is a purely aesthetic choice. Although, in truth, up until a few decades ago white gold was not so popular. In the last century, those who wanted a ring with white metal often chose a platinum jewel. A metal that, however, is also more difficult to work and rarer (as well as more expensive).

Bracciale in oro bianco, diamanti e zaffiro blu — Bracelet in white gold, diamonds and blue sapphire by Gismondi 1754

White gold has become very popular, and is used, in particular, for engagement rings. But, as we wrote at the beginning, not all white gold is the same. To be precise, there are white gold jewels made with at least fifteen different alloys. The main white gold alloys are obtained by adding nickel, in different percentages, or palladium and silver, but also copper and zinc. To these we must add rhodium, a metal that is very often used as an external patina, to make the jewel more shiny and whiter. Over the years, or due to a few scratches, this patina can be damaged. But just take it to a jeweler to make the jewel rhodium again.

Anello in oro bianco rodiato e diamanti della collezione Milano di Pomellato — Ring in rhodium-plated white gold and diamonds from the Milano collection by Pomellato

Does white gold cause allergies? It is very difficult for gold to cause a skin allergy. But it is not uncommon for the metals contained in an alloy with gold to cause some skin reactions. This happens more easily with jewelry that has a low percentage of gold, essentially those with a lower carat.

Anello trilogy in oro bianco e diamanti — Trilogy ring in white gold and diamonds

Is a white gold jewel worth less than a yellow gold one? The answer is no. The value of a jewel can be determined by the shape (for example, if it is of a famous brand), by the stones with which it is composed, for example diamonds or precious gems, and by the percentage of gold contained in the metal. That is, from karat gold: an 18-karat white gold jewel contains the same amount of gold as an 18-karat yellow gold jewel.

Bracciale Love in oro bianco e 10 diamanti — Love bracelet in white gold and 10 diamonds by Cartier

For which types of jewelry is white gold recommended? The answer is easy: for everyone. But, in particular, white gold makes diamonds stand out, as long as the stones have an excellent color, essentially they are classified from D to G. A diamond with a color from H to K or L (i.e. with a very slight tendency to yellow or gray) will probably stand out more on yellow gold: it will appear whiter. But the more colored diamonds, from the Light Yellow classification onwards, will once again be appreciated better on white gold.

Anello Atlas X in oro bianco con diamante di Tiffany — Atlas X ring in white gold with diamond by Tiffany

The 9 colors of gold

Published on November 14, 2020

Campus

Anelli con oro in tonalità bianco e apricot con tormaline di Annamaria Cammilli

Do you know why gold can have different colors? It can be white, yellow, pink, but also blue or purple. Learn about the colors of gold, even those that cause allergies ♦

It’s easy to say gold. The metal most used in luxury jewelry, considered the most precious asset for centuries, kept in ingots in bank vaults, actually has many faces. Because since it was used to make rings and necklaces, bracelets and earrings, gold has undergone several transformations. First of all, it can be more or less pure.

When a piece of jewelry is 100% gold it has 24 karats, while if it is 75% it is 18 karat. The remaining 25% is made up of other metals.

Trasformista, bracciale convertibile in oro 18kt e diamanti. Inciso manualmente utilizzando un bulino — Nanis 18kt gold and diamond convertible bracelet. Hand engraved using a burin

A percentage of 58% indicates a 14-karat alloy and, finally, when only 38% of gold remains, you have 9 karats. Furthermore, when it is alloyed with other metals, gold can change color, depending on the type of metal that is added. Everyone knows the three main shades: yellow, white and pink gold, colors that can be more or less intense. In reality, many jewelers use different percentages, which also give the gold completely different shades. In the diagram on this page we have summarized the main combinations that arise from the union of gold with other metals, in particular silver and copper.

In nature, in fact, gold has an intense yellow color, tending to orange, and is a very soft metal, which is easily deformed (1 gram can be transformed into a sheet of 1 square meter).

Anelli in oro giallo, rosa e brunito — Rings in yellow, pink and burnished gold

1 Yellow gold
The more intense yellow, the purer it is, as found in nature. The 99% pure gold is 24 carat and is exclusively deep yellow. Yellow gold is also the most used in jewelry. There are countries, such as India, which prefer gold in this color which is its natural hue. Yellow gold can also be of a less intense color, especially when alloyed with silver. Obviously the yellow gold with fewer carats, that is in alloy with other metals, has a more easily less intense color.

Collana in oro giallo di Amrapali — Yellow gold necklace from Amrapali

2 White Gold
It is an alloy with a white metal. When it comes to old jewels, it is often nickel (which however can cause allergies, on average to one in eight people), or manganese, palladium, but also silver. The alloy of gold and nickel is highly valued in jewelry because it makes the metal more durable for rings and brooches. On the other hand, gold with palladium is softer and makes setting stones easier. White gold is often not perfectly white, but has shades of yellow, brown or pink.

Anello Tourbillon in oro bianco e diamanti — Vhernier, Tourbillon ring in white gold and diamonds

3 and 4 Pink gold and red
It is an alloy that uses copper. It was very popular in Russia in the nineteenth century and has come back into vogue in recent years. The color difference between red and pink shades depends on the copper content. For example, a 18-carat gold red uses 75% gold and 25% copper. A 18K rose gold 75% gold, 20% copper and 5% silver. Some even add up to 15% zinc to give a dark yellow hue.

Tiffany, collezione T, bracciale in oro rosa — Tiffany T collection, rose gold bracelet

5 Green gold

Green gold was already known in ancient times: this shade is obtained by adding silver. The color of the metal with this alloy is greenish-yellow, sometimes also obtained with cadmium, a metal which, however, can cause allergies. The light green hue is obtained with an alloy of 75% gold, 23% copper, 2% cadmium. The more intense green color has instead 75% gold, 15% silver, 6% copper and 4% cadmium.

Anello in oro verde con cristallo di di berillio e diamanti verdi — Green gold ring with beryllium crystal and green diamonds

6 Gray Gold
The gray color is especially used for jewelry with a modern design. This color is obtained with a mix of yellow gold and palladium or silver, manganese and copper. If the other metals are added in minimal quantities, the color is closest to that of white gold.

Anello in oro grigio e diamante di Niessing — Gray gold and diamond ring by Niessing

7 Purple Gold
Violet or purple gold is obtained from an alloy that includes a particular type of aluminum. But purple gold is more fragile than other gold alloys and for this reason it is not often used: a sharp blow could cause the metal and, therefore, the jewel to shatter. Often purple gold is used only for small details of the jewels, together with gold (more robust) with other colors.

Jens Hansen, Replica ring, in oro rosa violetto — Jens Hansen, Replica ring, in violet pink gold

8 Blue gold
It is used rather rarely, but it is undoubtedly surprising. The gold of this color is obtained with an alloy with two metals little used in jewelry: alongside the yellow metal (46%), in fact, gallium or indium are added. in case, before buying it make sure you do not have allergies to these metals.

Anello in oro blu 14 carati con zircone — 14K blue gold ring with zircon

9 Black gold
It can be produced with various methods: by electroplating, with a rhodium or ruthenium patina. Or with a coating that uses sulfur and oxygen or with a forced oxidation by chromium or cobalt. More recently, black gold has been created by creating nanostructures on the surface and laser treatment. It is a high-impact color, often used by jewelers over the past decade.

Dionea Orcini, anello con oro nero, diamanti neri, zaffiri rosa — Dionea Orcini, ring with black gold, black diamonds, pink sapphires

In this graphic scheme taken from Wikipedia you can see the mix of metals that add a hue of color to gold. They range from the very deep pink, which has more copper (boulder corner on the right) to the white one, usually obtained by adding silver. The top tip of the triangle instead tends to yellow.

La composizione dei colori più comuni dell'oro — The composition of the most common colors of gold

Jewelry and allergy

Published on September 22, 2019

Campus

Do you have jewelry that causes skin allergy or irritation? Here’s how to solve your problem and avoid a nickel allergy ♦

Some argue that allergies are on the rise. As for jewels, unfortunately, they have always been a problem. The reason is simple: there are metals that cause allergic reactions when in contact with the skin. But there are also less dangerous metals for allergy sufferers, such as gold or steel.

Also read: How to avoid nickel allergies

This is why allergy sufferers choose gold jewelry. The yellow metal, in fact, is hypoallergenic, that is it rarely causes reactions in contact with the skin. But then, why does it also happen who wears a gold jewel to suffer from redness or irritation on the part of the body in contact with earrings, bracelets or necklaces?

Irritation caused by jewellery: this is an allergic reaction called contact dermatitis and is caused when pure gold is not used. It is a problem that, according to some calculations, affects 10% of women. This metal, in its natural state (24 carats) is too soft and deforms easily. For this reason, jewelers have linked it together with other metals, such as nickel. In this way the gold jewel becomes more resistant. In Europe, however, for over 20 years now the EU has issued a directive, which has become law in the adhering countries, which drastically reduces the use of nickel in jewellery. Nickel, however, continues to be present in jewelry made before the new rules. In Italy, for example, the use of nickel must not only be within the limits of the law, but also indicated on the label.

However, nickel isn’t the only metal alloyed in jewelry that can cause an allergy. In fact, it must be remembered that all 18, 14 or 9 carat gold jewels are alloyed with other metals. 18-karat gold, for example, means that out of 10 grams of metal, only 7.5 are pure gold, while at 14-karat this drops to around 50%.

How to avoid allergies. How to avoid nickel allergy? The first answer is obvious: if you buy a vintage jewel, ask the jeweler if the metal alloy of the jewel contains nickel.

If you already have jewelry at home that causes skin irritation or allergies, a simple trick is to use nail polish: brushed on the jewelry will avoid contact of the metal with the skin. You have to use the transparent one, of course. This system doesn’t work well with chain necklaces, but it can solve the problem with a ring or bracelet. Just cover the inside of the jewel, the one in contact with the skin, with the enamel. This prevents the nickel from coming into contact with the skin of the hands or wrist. Naturally it is necessary to verify over time that the enamel is not consumed with the use of the jewel.

Other metals. Another, more expensive way to avoid allergies is to choose platinum or titanium jewelry, two hypoallergenic metals. Copper, recommended by many, is certainly not a real alternative to gold: not only does it not have the same luster (even if it costs much less), but when in contact with sweat, it can ruin and dye the skin. Even silver, as long as it is sterling (92.5% pure) is often tolerated by those who have a nickel allergy, but must be constantly cleaned to prevent blackening.
Read also: Are cheap jewels dangerous?

The necklace that measures diamonds

Published on November 4, 2018

COLLANE/Diamanti/Showroom

Fred re-proposes his caliber-shaped necklace to measure the carats of the diamonds ♦

They gave you a diamond ring. Oh well, how big is the diamond? And has more carats than mine? Let’s say the truth: envy is part of human sins and, of course, a part is found in jewelry. Precisely to test who has this defect (which Dante in the Divine Comedy places in Purgatory: as punishment have their eyes sewed), the jeweler Fred Samuel has devised a truly amazing jewel.

The necklace has a pendant, an instrument for measuring the diamond carats: a “calibre a pierres”.

Naturally, within this tool, used by jewelers to speed up the work of carat control, one or more diamonds of different weight are found.
This series, among other things, is also linked to the anniversary of the fashion house, which turned 110 years old: conceived in the seventies, now the pendant has been revived in a numbered edition of only 110 pieces, as many as the birthday years. It was born, in fact, from Fred Samuel, born in an Argentinean family who traded in precious stones and pearls, his passion. Transferred to Paris Fred Samuel gave life to the Maison that bears his name and is located in rue de la Paix. Giulia Netrese

Bracciale Una Île d'Or — Bracciale Una Île d’Or

Bracciale in oro giallo della collezione Force 10

Anello in oro rosa e diamanti della collezione Force 10

Anello in oro giallo e diamanti della collezione Force 10

Orecchini Sugar Pain in oro rosa, diamanti, ametiste, quarzo

Collana Sugar Pain in oro rosa, diamanti, tormalina rosa, rubelliti

The glamor of The Graff Venus

Published on November 2, 2016

news

Graff has his Venus: a giant 118-carat diamond heart-shaped.
A black Venus for a white heart. It’s The Graff Venus, a 118.78 carat diamond, which was unveiled by London jeweler that has the widest collection of the highest quality stones. Graff, in fact, explained that this diamond is the largest in the world ranked as color D. And it is the maximum not only for color but also for clarity and cut. Classification D is, in fact, the highest on the scale by which the diamonds are judged: it means that it is perfectly colorless. And it is also at the highest level as clearly and is almost or completely free of impurities. Only between 1 and 2 percent of all natural diamonds have these features and this explains why they are so valuable. Added to this is that the heart cut is flawless, with perfect symmetry and an excellent polishing.
The Graff Venus is the largest cutted diamond that has been converted from the original stone, a piece weighing 357 carats records, discovered in 2015 in the Letšeng mine in Lesotho. And the size of the diamond has required special tools and new technologies to get to a perfect cut: to err is not allowed at this level. In fact, it took 18 months from the time of the discovery to complete the whole process. But it was worth it. Federico Graglia

The great big diamond

Published on November 20, 2015

news

Il diamante trovato nella miniera di Karowe, in Botswana

Who knows what and how many jewels will made from this super, ultra very big diamond. It is so great that not even seem a most precious gem: is a “monster” of more than two hundred grams, with a circumference similar to that of a tennis ball. It is the second largest diamond ever been extracted, and came from the mine Karowe, in Botswana. The stone weighs 1,111 carats, that is 222 grams, and is owned by the Canadian Lucara Diamond Corporation. It is the largest gem found in the last 110 years and the second gem quality ever extracted from a mine. Last July the Lucara sold a much smaller stone (341.9 carats) of the same type (IIa) for 20.6 million dollars, or 60 thousand dollars per carat. “It’s almost impossible to estimate a value for a stone so unique, since the value is highly dependent on the color, clarity and cut, and polishing,” says Edward Sterck, an analyst at BMO, specializes in the diamond industry. The record, for now, is still the 3,106 carat Cullinan diamond presented to King Edward VII in 1905 and after cutted into nine large gems, plus 96 smaller stones. One of them, weighing 317.4 carats, is in the British Imperial Crown. Federico Graglia

Il diamante grezzo della Lucara Diamond Corporation

La corona britannica: sulla fascia in basso il diamante Cullinan di 317,4 carati