The GIA Diamond Grading Report includes an assessment of the 4Cs – Color, Clarity, Cut, and Carat Weight – along with a plotted diagram of its clarity characteristics and a graphic representation of the diamond’s proportions. For standard round brilliant cut diamonds falling in the D-to-Z color range, the report also includes a GIA Cut grade.
Redesigned for 2014, GIA Diamond Reports offer thorough, unbiased analysis in an easy-to-understand format.
The GIA Diamond Grading Report includes an assessment of the 4Cs – Color, Clarity, Cut, and Carat Weight – along with a plotted diagram of its clarity characteristics and a graphic representation of the diamond’s proportions. For standard round brilliant cut diamonds falling in the D-to-Z color range, the report also includes a GIA Cut grade.
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Packing for your dream vacation and wondering if you should bring your favorite pieces of jewellery? Wonder no more as we provide you with tips for traveling with jewellery. Since fine jewellery has financial and emotional value, many travelers would rather leave it at home. But so long as you remember the following guidelines, you can safely travel with jewellery that is precious to you. 1. Photograph your jewellery: Photograph all the jewellery you plan to take. Should a piece get lost and is eventually found, you can use the photo to prove that it’s yours. Photograph the items together in a group and also on your person to prove ownership 2. Contact your insurance carrier: Notify your insurance company of your travel dates. Travelers often let their credit card companies know when they are traveling, and you should do the same when bringing jewellery 3. Carry your jewellery with you: Take your jewellery as a carry-on item. Never put them in your luggage – luggage can get lost 4. Organize using a pill box: Pill boxes are perfect for organizing and storing jewellery. They’re sturdy and inexpensive – and offer another benefit: they conveniently let you plan what you’re going to wear each day of the week. They’ll also protect your jewellery from getting damaged by the contents in your bag. 5. Pack your jewellery in plastic bags: Plastic sandwich bags are a great way to pack jewellery. Put each piece in its own bag, and then label the bag with a description of what’s inside it. This lets you quickly see everything that you’ve brought. Don’t store pearls in plastic bags for extended periods of time. 6. Pin your pieces: If the piece has a pin (like an earring or brooch), put the pin through the plastic bag so it won’t move. This prevents pieces from rubbing against each other, which can scratch and damage soft gemstones. 7. Don’t use cotton battening or cotton balls: Cotton battening and cotton balls leave fibers under prongs. Small plastic bags from the supermarket or $2 dollar shop is a much better choice. They won’t leave fibers on your jewellery and let you see what you’ve packed.
8. Bring a polishing cloth or an eye glass cleaning cloth: A soft cloth like ones used to clean eye glasses or a microfiber cloth are ideal for cleaning your jewellery before you wear it. 9. String chains through straws: Stringing your chains through straws prevents them from getting tangled. This simple trick can save you a headache at the hotel. 10. Don’t take too much: Sometimes less is more. You can still make a splash by bringing a select few pieces, while leaving the rest at home When you’re shopping for a diamond, its brightness and sparkle will draw you to the jewelry counter, and keep you captivated long after you’ve made your diamond purchase. Achieving maximum brightness and sparkle requires excellent cutting technique, which is reflected in the diamond’s cut grade. Of the 4Cs, no other ‘C’ has more impact on a diamond’s appearance. When people think of “cut,” they often think of the shape of a diamond rather than its cut quality. Cut is all about a diamond’s fire, sparkle, and brightness, and as a value factor, it refers to a diamond’s proportions, symmetry and polish; those factors that determine the cut quality or the fourth ‘C.’ In January 2006, GIA began assigning cut grades for round brilliant cut diamonds. Based on a comprehensive study that included 70,000 observations on more than 2,300 diamonds, GIA’s cut grading system assigns a diamond a grade of Excellent, Very Good, Good, Fair, or Poor. A number of complex factors are considered when evaluating a diamond’s cut grade: its proportions, the symmetry of its facet arrangements, and the quality of its polish or finish. The cut grade reflects the diamonds appearance. In this post, we’ll focus on proportions – represented by the diamond diagram that appears on all GIA Diamond Grading Reports and GIA Diamond Dossiers. By learning about proportions, you’ll also learn the basics of a diamond’s anatomy, and gain an understanding of one factor that goes into setting a cut grade, determined from a combination of measured parameters. Before we begin the Diamond Anatomy lesson, let’s be clear that no single proportion measurement is an indicator of what that diamond’s cut grade will be. GIA researchers proved that while every individual facet matters, a diamond’s appearance arises from the combined contribution of all its proportions. Even though all of a diamond’s parameters might be within the limits for a particular grade, a diamond might actually receive a lower cut grade when the parameters interact in a negative way to lessen a diamond’s appearance. Therefore, for round brilliant cut diamonds, GIA considers how a diamond’s proportions relate to each other, rather than considering individual proportions in isolation. Table Size: The table is the top horizontal facet of the diamond. The average table size is expressed as a percentage of the diamond’s average girdle diameter. While an ‘Excellent’ grade diamond will have a table size between 52 and 62 percent, other proportions are important too. Remember that GIA doesn’t consider individual proportions in isolation. Total Depth: The diamond’s overall depth from the surface of the table to the culet, expressed as a percentage of the average girdle diameter. Pavilion Depth: The pavilion is the lower portion of a diamond from the bottom edge of the girdle to the culet. The pavilion depth is expressed as a percentage of the average girdle diameter. A pavilion depth that’s too shallow or too deep will allow light to escape from the side or bottom of the stone. A well-cut diamond will direct more light upward through the crown. Pavilion Angle: Pavilion angle is another important dimension of the stone, especially as it relates to a diamond’s brightness. It is the average of the angles formed by the diamond’s pavilion main facets and its girdle plane. This should fall between 40.6 and 41.8 degrees to be considered “Excellent,” providing other parameters also fit their proper ranges. Crown Height: The crown is the upper portion of the diamond, from the top edge of the girdle to the table. The average crown height is expressed as a percentage of the average girdle diameter. It can affect both the dispersion and brightness of a diamond. Crown Angle: The crown angle is the angle that’s formed where the bezel facets meet the girdle plane. The crown angle in a well-cut diamond will be within 31.5 to 36.5 degrees. The crown angle has a large effect on the face-up appearance of a round brilliant cut diamond. The best range of crown angles provide a route for exiting light dispersion, as well as additional contrasting directions for entering light. Star Length: The horizontally projected distance from the point of the star facet to the edge of the table, relative to the distance between the table edge and the girdle edge. A well-cut diamond will range between 40 to 70 percent, when other parameters are within the correct ranges Girdle Thickness: The girdle is the middle portion of a diamond, a narrow section separating the crown from the pavilion, and functions as the diamond’s setting edge. The girdle thickness is described as a range from its thinnest to thickest areas. A thick girdle is less desirable because it unnecessarily adds weight to the stone where it matters the least (making the diamond appear smaller). An extremely thin girdle is sometimes referred to as a knife-edge, and results in a diamond that is more fragile and susceptible to chipping. Therefore, a girdle that is “medium to slightly thick” is preferred. Lower Girdle / Half Facet Length: This ratio is measured by calculating how long the lower girdle facets are relative to the length of the pavilion. This defines the contrast of a round brilliant cut diamond, which controls the brilliance of a diamond. The well-cut diamond will range between 65 to 90 percent. Diamonds with longer lower half facets will have a little more scintillation. Culet: The culet is the small facet at the bottom of a diamond intended to prevent chipping and abrasion to the point. The culet size can affect face-up appearance and it’s described as the average width of the facet. Size is expressed as none, very small, small, medium, slightly large, large, very large, and extremely large. When there is no culet, it is sometimes referred to as a pointed culet. Preferably the culet will not be visible with the unaided eye, and when described as none (no culet), very small or small on a GIA report, it falls in the excellent range. Now that you understand diamond proportions, you’re one third of the way to learning about the factors that influence a diamond’s cut grade. We’ll cover finish, polish, and symmetry in later posts.
An “Excellent” in GIA’s cut grading system will tell you what most people prefer. However, our best advice as you shop around is to do what GIA researchers did – look at a number of diamonds. After all, beauty is in the eye of the beholder and your own eyes will tell you whether or not a diamond’s cut is right for you! At NZ Diamonds we only sell GIA certified diamonds. We can source the exact diamond shape, diamond carat weight, diamond colour, diamond clarity & most importantly the exact diamond cut you are looking for. Thanks once again to GIA for their excellent insight into diamond anatomy! Blue diamonds are extremely rare, exquisitely beautiful, and rich in old folk lore. This special combination has made them coveted by diamond lovers and jewelry connoisseurs. How rare are blue diamonds? To find that glittering needle in the haystack, tons of ore have to be unearthed. And when a blue diamond is found, you can imagine the excitement it causes. But what make a blue diamond blue? The answer is a diamonds exposure to either Boron, Radiation or Hydrogen. The presence of boron impurities is most often responsible for the colour of natural blue diamonds. The centre photo below shows a natural blue diamond with boron impurities. Some blue diamonds are naturally coloured by exposure to radiation. These diamonds usually appear with a more vivid green-blue colour. Diamonds coloured by their association with hydrogen are described as gray-violet to gray-blue (pictured below on the right). Blue diamonds were first found in India and were brought to the West by the gem dealer Jean-Baptiste Tavernier in the 17th century. He sold a very large blue diamond to King Louis XIV of France. The diamond was originally known as the Tavernier Blue but when re-cut to become a part of the French crown jewels it became known as the French Blue. The diamond was stolen in 1792 and re-cut to avoid detection and was then eventually purcahsed by Henry Philip Hope in 1830. Since being purchased the diamond gained the reputation of being cursed and has often been thought to be associated with the deaths of very difficult lives of some of its owners. This diamond is now known as the very famous Hope diamond and is now housed in the Smithsonian Natural History Museum in Washington, D.C. Another historically notable blue diamond is the 70.21 ct Idol’s Eye. This diamond was probably found in India’s Golconda district sometime in the early 17th century, but its first historic record was its sale to a mysterious buyer at Christie’s London on July 14, 1865. In 1906, it was known to be in the possession of Abdul Hamid II (1842–1918), the 34th Ottoman Sultan. India was historically the source for blue diamonds but within the last several years, notable blue diamonds have been found at the Cullinan Mine in South Africa. A few other South African mines have produced blue diamonds and some are occasionally found in Sierra Leone, Borneo - which is off the coast of Indonesia, and Brazil. Blue diamonds are absolutely beautiful but they do present unique cutting challenges. The rough diamond is usually asymmetrical which can make it more difficult to determine how the stone should be cut and polished. Rough blue diamonds can also have colour zoning – areas that have more blue than others. Cutters want to get the best even colour out of a diamond, while retaining as much weight as possible, and colour zoning can make this balancing act extremely difficult. With understanding of a subject often comes a deeper appreciation. Now that you know some of the secrets of blue diamonds, you may find them even more beautiful.
GIA’s online Gem Encyclopedia has an entire entry devoted to coloured diamonds. Thanks to GIA Blog for this fabulous article and photos! http://4csblog.gia.edu/ The Pink Star, a GIA-graded 59.60 carat Fancy Vivid pink diamond, sold for $83.2 million at a Sotheby’s auction Nov. 12, 2013 in Geneva. Photo courtesy of Sotheby’s.
Pink diamonds are definitely on trend with celebrities and diamond connoisseurs alike, and with good reason! These diamonds are not only very rare and stunningly beautiful, if they are GIA certified they will also hold their value and as the above auction shows can be an excellent investment! Only one out of 10,000 carats of fashioned diamonds displays fancy colour, and a diamond’s chances of displaying intense colour are even lower – one in 25,000. The main source for natural pink diamonds is the Australian Argyle mine. Unfortunately for most but fortunate for the select lucky few who own one, it is believed this mine will be exhausted by 2020. Add all the above together and you have the recipe for a serious trend! Natural Pink Diamonds, gorgeous, beautiful & very rare, if you would like to own one contact NZ Diamonds today and we will source a diamond to meet your budget. The Elizabeth Taylor Diamond was originally known as the Krupp diamond, but the name was adjusted to reflect the status of one of the most iconic actors of the 20th century. The Asscher cut diamond is a whopping 33.19 carats and is graded by GIA as D-color & VS1 in clarity. The diamond was a surprise gift from Richard Burton to Elizabeth Taylor in 1968, and without a doubt became the most iconic piece of jewelry in her diamond collection. The diamond is set in a platinum ring and accented by two tapered baguette-cut diamonds. As a testament to her love for the diamond she wore the ring nearly every day. Due to her obvious love for this diamond, after her death in March 2011 the ring became one of the most anticipated pieces to be auctioned at the 2011 Christie’s auction of Elizabeth Taylor’s jewelry. The diamond sold for an astonishing $8.8 million – far exceeding the $2.5-$3.5 million estimate. However this diamond was not the biggest diamond Richard Burton gave to Elizabeth Taylor. He also gifted her a pear shape diamond of an astonishing 69.42 carats. The diamond known as the Taylor-Burton Diamond was the worlds first ever million dollar diamond and was worn by Elizabeth Taylor as a pendant. Elizabeth Taylor divorced Richard Burton for the second time in 1976. In 1978 Elizabeth Taylor sold the Taylor-Burton diamond for five million dollars. She then used all of the money to build a hospital in Botswana, proving she was not just one of the most beautiful women of our time but also a very thoughtful and generous one. As I have previously blogged about colour is one of the four c's that you should consider when you are purchasing a diamond. The majority of you will understand the GIA colour grading scale which rages from D - Z. D being the very best colour or colourless and Z being at the opposite end of the scale showing a yellow or brown tone and saturation.
But how do we actually view colour in a diamond? When light enters our diamond a process called selective absorption occurs. Selective absorption is what offers colours to all things. With diamonds it does this when visible white light enters the diamond enabling the gem to absorb some of the wavelengths, while also transmitting wavelengths to the viewers eye. Absorption bands or lines in the spectrum of of an incandescent source are seen through the absorbing medium - the diamond. If little or no colour is absorbed by an object then it appears colourless or white. On the other hand if the entire spectrum of colours is absorbed, the object will appear black. In-between there are an infinite number of colour possibilities. In diamonds it is the presence of nitrogen atoms (or other atoms of impurity) which determines the level of absorption, and therefore the color of the diamond. The less impurities there are in your diamond the whiter or more colourless it will appear. D colour diamonds are very rare but we specialize in providing our clients with these very rare GIA certified diamonds. Diamond Fluorescence is a naturally occurring phenomenon that enables a diamond to emit a soft glow, usually blue, when it is subjected to ultraviolet light. You may find that when you stand near a blue light or ultraviolet light you notice peoples teeth and white of their eyes become brighter or appear to glow. This is the same effect that UV light has on some diamonds. Fluorescence is what the visible light is called that the diamond emits when exposed to the UV rays. On a GIA diamond grading report, fluorescence refers to the strength or intensity of the diamond’s reaction to the UV light. The GIA scale uses the following grades: None, Faint, Medium, Strong, Very Strong. The fluorescence grade will also include the color, e.g., “Medium Blue”. The most common color of fluorescence is blue, but other colors are possible depending on the trace elements within the diamond’s crystal structure. Diamond fluorescence is actually quite common and occurs in bewteen 25 - 35% of all diamonds. Of the diamonds that exhibit fluorescence 95% emit a blue glow. Does Fluorescence matter?
The first and most important thing to remember is that fluorescence is almost always an invisible property of the diamond. In the vast majority of situations, fluorescence has no impact at all on the visual beauty of a diamond. Except for the grade noted on the diamond’s certificate, the typical diamond wearer will never see the fluorescence of their diamond in the course of a lifetime. This is true of diamonds with a grade of Faint or Medium fluorescence. In fact, diamonds in the near colorless and faint yellow ranges that exhibit some fluorescence will actually appear whiter than stones of equal color without fluorescence. GIA studies show that for the overwhelming majority of diamonds, the strength of fluorescence has no widely noticeable effect on appearance. In the GIA Fluorescence Study, it was found that the average person could not make a distinction between a diamond with fluorescence and a diamond without. In many instances, observers prefer the appearance of diamonds that have medium to strong fluorescence. In rare cases, some diamonds with extremely strong fluorescence may appear hazy or oily; fewer than 0.2% of the fluorescent diamonds submitted to GIA exhibit this effect. Should I purchase a diamond with Fluorescence or not? The preference to buy a diamond that exhibits fluorescence is a personal one, as a diamond’s appearance must be taken as a whole. Other factors can influence color appearance more strongly than fluorescence, such as how the diamond has been cut, whether the diamond is viewed in natural or artificial light, and even what you’re wearing on any given day. Why do some jewellers recommend avoiding any type of fluorescence? Quite simply it is easier to tell a customer that fluorescence is bad and to avoid it than to actually educate themselves or their clients on the facts. The bottom line on fluorescence is that in the Faint and Medium Blue ranges, it is not a characteristic that should cause any concern to you as a buyer. |