26 Sep 11 Color Grading of Diamonds
Most people don’t know this, but diamonds come in every color of the rainbow. Diamonds are made of carbon. When nature adds different elements to the carbon it creates different colors. Adding boron will give the diamond a blue color, nitrogen makes them yellow, hydrogen gives violet hues and so on. Most consumers are looking for the traditional colorless or near colorless diamond that is used in bridal and fashion jewelery in retail stores.
Diamonds are graded on a color chart that is recognized around the world. The chart starts with the letter D (think D for Diamond) and runs all the way to Z.
D, E, F, G, H, I, J, K … Z
Starting with the letter D and going to F are what are called colorless diamonds. These diamonds have an absence of yellow in them and are more rare to find in nature. They offer a beautiful white appearance but of course cost more because of the rarity of them.
Diamonds graded G-J are called near colorless.
These diamonds will have start to have a very slight tint of yellow and are more common in the marketplace. Typically all fashion pieces like necklaces, earring, bracelets, etc. are going to be in this quality. One of the reasons why is because a fashion piece tends to have many diamonds on it and if they were all colorless it would make the price spike fairly quickly. Near colorless diamonds offer affordability and allow the jewelry to have a higher total carat weight.
Anything running from K-Z is going to have a visible yellow color. The closer you get to Z the more yellow a diamond will have. It is around the Z range that you will start to see what some refer to as Canary diamonds. Just as a D color is rare, a Z is the same way.
The price for a diamond that starts to get close to Z with an intense or vivid yellow color starts to increase because of it’s rarity.
A jeweler trying to determine the coloring of a diamond will have a set of what are called master stones. These stones are made of a synthetic stone called cubic zirconia (CZ). These CZ’s are shaded from D-Z just as if they were real diamonds. The jeweler will hold a real diamond next to these master stones to determine the coloring of it. To tell the difference between a G and an H diamond is very difficult, even for a seasoned jeweler. Having these master stones is a great visual reference point for getting a more exact idea of what color the diamond is that is being looked at.
As stated before, most fashion jewelery is near colorless which is standard. But when you start shopping for an engagement ring, you’ll need to pay closer attention to the color of the diamond you’re thinking of purchasing. This is going to be the center stone of her engagement ring that she’ll look at forever and you sure don’t want it to be a dull or murky yellow. Here are a few pointers:
If you’re going to be putting the diamond into what’s called a solitaire (a thin band of gold or platinum with just the one diamond on it, no side diamonds) you need get a diamond in a color that’s going to be complimentary to the metal of the band. If you’re getting a white gold or platinum solitaire you need to get an H color or better. Anything I or below will have a yellow tint that will contrast with the white color of the metal and will make the yellow in the diamond very visible. If you’re going with yellow gold you can usually get away with anything because the yellow in the metal will blend with the yellow in the diamond. Keep in mind though that if you purchase a colorless diamond, even a D, and you put it into a yellow gold band, you might see some of the reflection of the yellow metal bounce up into the colorless diamond. It’s a very very faint reflection but if you think this might bother you, save the money and go for a G-H, they will blend and hide the reflection.
If you’re purchasing a ring that’s going to have side diamonds, you need to get a center stone that is comparable in color to the sides. There’s no need in buying a D if the side stones are an I. The beautiful whiteness of the D will make the side diamonds look dirty.
I worked in the jewelery industry for 7 years and have sold engagement rings from a couple hundred dollars to over fifteen thousand dollars. Here is my opinion:
Go for a G color. The reason is because it looks just as white as a colorless diamond without having to pay the price for one. Most people who purchase a colorless are doing so because it’s at the top of the chart and “high quality”. Almost 95% of the time that I would hold 2 diamonds next to each other, one an F and one G, and asked the customer to tell me which was which, no one could ever tell the difference. Typically you have to have a 2 color grade difference to see a change in color. That’s why jewelers use master stones, it’s hard to tell a G from an H or even more so from an E to an F. As an average consumer (even myself most times) you’ll usually have to strain to see the visible difference between an F and G but not the difference in the jump in price . The reason is because you’re jumping from the near colorless category to colorless. No real visible change, but a category change. Save your money and buy a G. It’s not like you’ll be walking around all day with 2 diamonds comparing them. A G is affordable, offers a wonderful color (or lack thereof) and will work with any ring you put it into, whether it’s a solitaire in yellow or white gold or it has side diamonds.
29 Aug 11 Color Treated Diamonds
Many people are starting to favor the fancy, vivid colored diamond gem stones over the traditional transparent, or white, diamond. Some diamonds are found in their natural colors when they are mined, others become colored by gemologists and jewelers during a treatment process. In order to make them more affordable to the average consumer, companies have begun color treating diamonds of lower grades in order to take a less desirable yellow or brownish tinted diamond and make it into a beautiful, brightly colored diamond.
Colored diamonds can be treated by a process called irradiation, which uses a high heat system to alter the color of a diamond. Other diamonds are treated by painting.
Fancy Colored Diamonds:
While many diamonds are inspected and valued based on their colorless qualities, there are people who prefer the fancy colored diamonds that come in vivid hues of greens, yellows, reds, pinks and all the different colors in between.
Some colored diamonds are that way naturally. If a diamond has nitrogen in it, it often has a yellow tint to the stone. If the gemstone has been effected by radiation, the gem may turn green.
Other colored diamonds have been treated to obtain their color, and this allows people with lower budgets to purchase the fancy colored diamonds. Gemologists have found ways to alter the colors of diamonds to get any shade or hue desired.
The grading process for colored diamonds is slightly different than that of the transparent diamond. First, a colored diamond is graded based on the primary hue, the blue or pink or red color that makes up the majority of the diamonds color. Second, they are graded based on the intensity of that color. A very intense, naturally colored diamond is more rare than a less intense diamond, and therefore more expensive. A treated diamond will cost less than a naturally colored diamond in most instances.
Synthetic Diamonds:
Most diamonds are found and mined by miners, but more recently, scientists have come up with ways to create synthetic diamonds. While a synthetic diamond is still a “real diamond”, they are created within a laboratory instead of by nature in a mine.
Colored Diamond Names:
Because fancy colored diamonds come in so many different shades, it can sometimes be difficult to interpret the name of the diamonds color. Often, you’ll find two colors labeling the shade of a diamond, such as greenish blue. Each name has a primary color description, and some have a secondary color description. If a diamond is called “blue diamond”, you can tell it will be a blue shaded diamond gemstone. If the diamond is called “greenish blue”, you may wonder what that means.
Is the diamond blue, or is it green? The color that is described with the “ish” at the end is considered the secondary color, and the other color, in this case blue, becomes the primary color. So a greenish blue diamond is mostly blue, with specks of green seen throughout the stone. If you come upon a diamond labeled “brown red”, then the diamond will have equal amounts of both colors seen through the stone.
28 Jul 11 The Splendor of Diamonds
The Diamonds in the Smithsonian’s Exhibit
The Smithsonian’s Splendor of Diamonds was a display of seven of the rarest diamonds in the world. The diamonds ranged in size from 5.11 carats to 203.04 carats. The exhibit ran from June 27, 2003 to September 15, 2003. The seven diamonds displayed were the Allnatt, the Millennium Star, the Ocean Dream, the Moussaieff Red, the Heart of Eternity, the Steinmetz Pink, and the Pumpkin Diamond.
The Allnatt is a cushion-cut, Fancy Vivid Yellow diamond, as rated by the Gemological Institute of America (GIA.) It is currently owned by the SIBA Corporation and has a mass of 101.29 carats. Its yellow color is due to a certain concentration of Nitrogen impurities within the carbon structure. The Allnatt’s rarity comes from its size and its color- few diamonds with a mass greater than 100 carats can retain such a vivid color, which makes these diamonds perfect for money back guarantee diamonds, since nobody would want to return such a unique diamond.
The Allnatt Diamond
The De Beers Millennium Star is the sixth largest known colorless diamond of gemstone quality that has ever been found.
It is the second largest flawless, colorless pear cut diamond. The lack of color in the Millennium Star means that it is made entirely from crystallized carbon. There are no impurities from other elements, no defects in its structure, no irradiation during the growth process.
The Millennium Star is owned by the De beers company. It originated from the Democratic Republic of the Congo in the early 1990s. The original diamond was 777 carats (155.4 g.) It went to the Steinmetz group three years to laser-cut and polish the rough crystal to its 203.04 carat pear shape.
There was some debate concerning whether the diamond was a “blood diamond” or a “non conflict diamond” since it was from an area rich in war diamonds, but this truth was never proven and cleared the Kimberley Process.
The Ocean Dream is a 5.51 carat (1.102 g), Fancy Deep Blue-Green diamond, as rated by the GIA. It is one of the rarest diamonds in the world, for it is the only natural diamond known to the GIA to be of a blue-green color. Blue green is normally seen in synthetic or artificially altered diamonds. In order to achieve such a hue, the diamond color must be altered via irradiation. The Ocean Dream was exposed to millions of years of the earth’s natural radiation- causing its blue-green color.
The Moussaieff Red is a 5.11 carat (1.022 g), trilliant cut, fancy red diamond, as rated by the GIA. Red, especially a deep red, is one of the rarest hues found in a diamond. The Moussaieff is the largest Fancy Red diamond that the GIA have ever seen. It was found by a farmer in Brazil in the mid 1990s, where it was purchased as a rough crystal of 13.9 carats (2.78 g) by William Goldberg Diamond Corp. The crystal was cut, polished, and named the Red Shield. It was bought by the Moussaieff Jewelers Ltd and renamed.
The Heart of Eternity is a 27.64 carat (5.528 g), heart cut, Fancy Vivid Blue diamond, rated by the GIA. This diamond originates from South Africa. It was cut by the Steinmetz Company, who sold it to the De Beers Company. The blue color is due to boron impurities in the carbon structure of the diamond. Very few “blue” diamonds are of such vivid color, for often the boron is only located in certain sections of the stone, or the color is extremely desaturated and mixed with shades of gray.
Like many diamonds, the Steinmetz Pink originates from South Africa. It is owned by Steinmetz Company, has a mass of 59.60 carats, and is internally flawless. The GIA diamond rings Institute (the world’s foremost authority on diamonds) confirmed it to be the largest Fancy Vivid Pink diamond that they had ever seen. It took twenty months to prepare, cut, and polish.
At 5.54 carats (1.108g), the Pumpkin Diamond is one of the largest Fancy Vivid Orange diamonds that the GIA have ever rated. It originated from the Central African Republic, where it was cut and polished by William Goldberg. The Pumpkin Diamond was bought by Ronald Winston for 1.3 million dollars, though it is currently valued at three million dollars. It was set in a ring between two white diamonds for actress Halle Berry to wear to the 2002 Oscars.
Allison Ryan is a freelance marketing writer from San Diego, CA. She specializes in gemology, GIA diamond rings, and where to find a non conflict diamond. For a breathtaking selection of diamonds and to learn more about this beautiful stone, stop by http://www.diamondwave.com/.
20 Jun 11 Hpht Diamonds
History of HPHT
The history of HPHT treatments dates back to 1955, when the General Electrical Company 1st discovered the process for creating diamonds within the laboratory. This led to the creation of HPHT process, whereby GE initial created a press where the required pressure and temperature might be maintained for the process. One factor led to a different and HPHT treatment evolved through numerous presses like the tetrahedral, BARS and finally the cubic press. What began as an experiment for diamond color modification in artificial diamonds has today evolved into usage for natural diamonds also.
Usage of HPHT Diamond Enhancements HPHT treatments primarily serve 2 functions
?Creation of artificial diamonds
?Color modification in natural diamonds
Creating artificial diamonds: To obtain artificial diamonds, carbon is put within a grapite capsule. A seed is then inserted into this capsule and a catalyst is added. The diamond grows on the seed whereas the catalyst allows the crystallization to require place.
Color modification: Completely different sort of diamonds react differently when exposed to HPHT treatments and a vary of colors are obtained. For instance, diamonds containing aggragated nitrogen, when exposed to HPHT will cause it to become single substitution nitrogen. In such cases, diamonds having green, orange and yellow hues will be created. In diamonds where nitrogen is negligible, the method is typically used to supply colorless diamonds. Therefore brownish diamonds when HPHT processed can obtain a colorless hue. A light pink color could additionally be obtained in some cases. In case of diamonds with negligible nitrogen and presence of boron, HPHT will alter the color. Therefore brownish diamonds will lose the brown tone and boron can make the stone bluish in color.
Popular presses used for treatment
Belt presses: This was the initial type of press used for treatment. Here pressure is formed by the usage of 2 high strength pistons that provide equal pressure in opposing directions on a sample. A series of rings surround the sample in order to contain the pressure.
Torid press: During this method, the 2 pistons apply pressure in an exceedingly single vertical direction.
Cubic press: This uses many pistons that provide pressure from completely different directions. It’s also known as a tetrahedral press.
Procedure of HPHT
If a client intends to convey diamonds for this treatment, the subsequent procedure is used,
?The stone is 1st inspected by diamond experts for cracks, fractures etc. Stones also are subject to chemical analysis using scientific equipment. Once it is confirmed that the treatment can be undertaken, the same is informed to the customer.
?Relying upon the properties of the stone, the color that may be obtained when treatment is deciphered and the customer is informed concerning the same.
?Pressure of over 1,000,000psi is applied by placing the stone in an inside pressure medium that distributes the pressure on the complete diamond equally.
?The internal pressure medium is placed into a heat generating sleeve where temperatures start at 1800 degrees centigrade.
Pricing of treatments: Price for these treatments varies with the scale of the diamond. Additionally the overall number of stones given and additional services like repolishing are charged extra. Whereas these treatments are expensive,
Organizations and HPHT
Because HPHT is controversial, totally different bodies follow different pointers for HPHT. As per the Federal Trade commission, HPHT treated diamonds should be disclosed to the user. General Electrical follows this norm and all diamonds that are HPHT treated are laser inscribed with the terms ‘HPHT PROCESSED’, IRRADIATED. If GIA notes diamonds to be HPHT treated, it additionally specifies them as ‘HPHT ANNEALED’ or ‘Artificially Irradiated’. Such details are displayed prominently on the grading report below ‘origin’ within the ‘color’ section of the report.
Execs and cons
The HPHT treatment of diamonds is a controversial issue as a result of it has each blessings and disadvantages. These are more discussed as under.
Benefits
?The treatment is permanent and diamonds are stable in the conventional conditions of wear and care.
?It can dramatically alter the colour of brownish diamonds to create it more appealing. Light-weight brown color diamonds will be rendered virtually colorless using this process.
Disadvantages
?The method causes surface graphitization and therefore the diamond desires to be polished to get rid of it.
?It is tough to differentiate between regular natural diamonds and HPHT treated diamonds.
?It will cause marginal weight loss during a diamond.
?It can scale back the clarity of the stone.
Disclosure
As HPHT has become a lot of commercially on the market, today there are various ways on the market to detect if your stone has been HPHT processed or not. At the fundamental level diamonds over 0.five carat will solely be HPHT treated. A trained gemologist may use equipment like the SSEF spotter and crossed polarization filter to detect the same. DiamondSure is additionally used to separate cape diamonds from the rest. At the following level FTIR and UVVIS spectroscopes are used and synthetic and PT treated diamonds will easily be identified ere. Besides this, renowned laboratories have several alternative proprietary procedures that they use to spot such diamonds.
With all refined equipment it continues to be difficult to detect HPHT processed diamonds at many instances. It’s so necessary that you purchase diamonds from a trusted vendor on-line or offline. Diamonds accompanied with a certificate from a reputed laboratory like GIA conjointly guarantee that diamonds are completely natural. You’ll additionally select signature or prime of the road branded diamonds to shield yourself. Finally, if you cannot afford GIA stones, create positive to choose a diamond that’s in the course of a certificate from a renowned laboratory.
14 Jun 11 How Are Lab Diamonds Created?
Lab diamonds are created using a technological process whereas natural diamonds are created using a geological process. Synthetic diamonds are produced using High-Pressure High-Temperature synthesis and Chemical Vapor Deposition which explains why they are also known as HPHT diamonds or CVD diamonds. Beautiful and every bit as spectacular as mined diamonds, these stones don’t come with a stigma or an expensive price tag. In fact, one of the reasons why they are so popular is because they’re affordable. You don’t have to be a celebrity to own a large, beautiful lab diamond.
A synthetic diamond is the hardest material known. Like mined diamonds, it can cut glass. To the untrained eye, there is little difference between the two. That’s because they’re similar in almost every way imaginable.
The biggest difference is how they are cut and how they are obtained. In places like Sierra Leone, natural diamonds are sold to fund illegal activities. They are acquired through unethical means and all of the mining has wreaked havoc on the environment. Without a way to support themselves, many citizens of the African country find it difficult to survive. If you want a clear conscience, you’ll stay away from “conflict diamonds”.
Lab diamonds are often cut by hand. This ensures that your stone is flawless when you buy it. The same cannot be said about mined diamonds. The way that the diamond is cut is largely determined by its cost. This means that smaller stones may not be as perfect as other larger stones. That is never the case with synthetic diamonds. Each one is cut using great care and accuracy. Precision is of utmost importance because appearance is everything when it comes to lab-grown diamonds.
Whenever you’re in the market for a beautiful piece of jewelry, why not consider synthetic diamonds? Attractive, stylish, and long lasting, they make the perfect addition to antique and modern settings. You can choose to have them placed in a pair of earrings, a ring, a bracelet, necklace or pendant depending on your own personal style and preference. This allows you to express yourself in whatever way that you see fit. Other people can’t help but notice how spectacular and brilliant your lab created diamond looks. That’s why you shouldn’t keep yours under wraps. Wear it out wherever you go.
