The Impact of Fluorescence on Beauty & Value

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1 Two out of every three diamonds have fluorescence to some degree. Strong fluorescence causes the diamond to look oily and milky in sunlight. The selling of diamonds requires a presentation of each of the four Cs (cut, colour, clarity and carat weight). But a fifth factor Fluorescence - often plays a role in the pricing, marketability and the discussion may arise in a sales presentation. The Impact of Fluorescence on Beauty & Value Fluorescence is caused by trace impurities in the diamond and means that a diamond will glow under an ultraviolet lamp when illuminated. This reaction to ultraviolet light varies in strength and is noted as: None, Faint, Medium, Strong, or Very Strong. A diamond can be exposed to ultraviolet light from the "black lights" often found in nightclubs, the drying lights used in nail salons, office fluorescent lighting or even direct sunlight. Only those diamonds with inert, faint or medium fluorescence meet our strict guidelines for Bridal & Diamond Solitaire Jewellery. Top: uncut diamonds under normal lighting and under ultraviolet light. Bottom: Notice the varying strength of the strongly fluorescent diamonds (below). How does Diamond Fluorescence affect price? The impact of fluorescence on price depends on it s noticeability. For some higher colour stones, fluorescence gives the stone a milky white appearance, which greatly lowers value. In some instances, the fluorescence is hardly noticeable and has minimal impact on the stone's brilliance and value. This dark light photograph illustrates several diamonds that fluoresce. Sometimes this can be used as an identifiable trait to a particular jewellery article. Before grading reports, there was a widespread preference for diamonds with fluorescence and they often sold at a premium to diamonds without fluorescence. This was due to the fact that colourless diamonds with strong blue fluorescence look similar to the very rare diamonds that actually have blue body colour. The term "blue-white" became a status symbol and referred to colourless (D, E and F) diamonds with strong blue fluorescence.

2 MARQUISE OVAL TRILLIANT HEART THE FANCY CUTS (top) ARE VARIATIONS OF THE MODERN BRILLIANT. THE FACET COUNT & FACET SHAPE ARE VERY SIMILAR TO A ROUND BRILLIANT, BUT WITH DIFFERING GIRDLE OUTLINES. Misshapen natural diamond crystals called macles are often cut into fancy shape diamonds. Any diamond other than round is correctly termed fancy shape. All of the 4C's apply as they do for a round diamond. However, there are other considerations that are important for fancy shapes. They are the overall appearance of the girdle outline, the degree of the "bow tie" effect and the length-to-width ratio. Currently there is no widely accepted "ideal" range of proportions for fancy shaped diamonds. Probably the most important aspect for a fancy cut is the general appearance to your eye and that it is appealing and symmetrical. In many fancy shaped diamonds (marquise, pear, oval, emerald and heart shaped), the pavilion facets may not culminate at a point at the tip of the pavilion as they do for a round. Instead, they form an edge, called the "keel line." This line should be centered in the diamond and this "culet" should still be as small as possible. PRINCESS MODIFIED RADIANT OLD MINE CUT Many fancy cuts are modified from patented cutting styles. As a general rule, pointed corners are variants of the princess, cut corners variants of the radiant and rounded corners of the cushion cut are variants of the original old mine cut. Cutting styles are categorized into three basic types: step-cut, brilliant-cut and mixed-cut. The step cut has parallel rows of facets that resemble the steps of a staircase and are usually foursided and elongated. The emerald, asscher and baguette cuts are examples of this cut. The most common brilliant cut is round. Other examples of brilliant cuts are heart, oval, marquise, and pear. All brilliants have facets and are admired for their fire and sparkle. The mixed cut has both step and brilliant cut facets. In the last 20 years, mixed cuts featuring step cutting on the crown and brilliant cutting on the pavilion have become very popular. Examples of mixed cuts are radiant and princess cuts. FANCY SHAPES Girdle width will vary between greater extremes on some fancy shapes compared to the round brilliant. These include the marquise, pear and heart, where the girdle tends to be thick or extremely thick at the tips of the stone and in the cleft of the heart-shaped cut. Also, the princess cut, which has square corners, may have an extremely thin girdle in these areas. Since the girdles vary with greater frequency in fancy shapes, attention needs to be paid to extremely thin and extremely thick girdles to avoid danger of chipping or excessive weight. BOW TIE The bow tie effect, observed with the unaided eye, is frequently found in marquise, oval, radiant, pear and some heart-shaped diamonds, and is considered to be a negative factor if prominent. It arises from the variations in the pavilion facet angles required in cutting stones which are longer than they are wide. The bow tie effect is caused by light leaking out of the bottom of the diamond. The bow tie looks like two dark triangular shapes joined at the point in the center of the stone and looks like a man's black bow tie. While almost every elongated stone has some "bow tie" shadowing, in better fancy cuts this is minimal or even absent. The pear shape exhibits an obvious bow tie and the Crisscut shows other shadowing elements. The bow tie or other shadowing problems are often evident in many fancy shapes. A fancy shape is often the cutters choice with a fancy colour diamond. The usually deep pavilions allow for greater colour concentration.

3 FANCY SHAPES Old Mine 2. Old European 3. Rose Cut Old Mine & Old European cut diamonds carry an additional value premium if they are high clarity and colour. Very few of these stones have survived the practice of recutting so they are much rarer. OLDER CUTTING STYLES AND SHAPES It is not uncommon to find in estate and antique jewellery older styles of cut diamonds. Although there are literally hundreds of styles some of the most common are the Old Mine Cut, Old European cut, Swiss cut and Rose cut, Old mine cut :sometimes called old miner are an early form of a brilliant cut diamond. It has a squarish or cushion shaped girdle outline, a high crown, small table, a deep pavilion and a very large culet. This is the foundation cut style for the cushion. Old European cut: the earliest form of a brilliant cut with a round girdle. It usually has a small table, heavy crown and a great overall depth. Culets are usually large. Swiss cut: round brilliant cut with 16 crown and 16 pavilion facets. Most Swiss cuts are in the 0.03 carat to 0.17 carat size. Rose Cut: has a flat base and can be circular in outline. Some rose cuts will follow the outline of the original rough so you may see ovalish and squarish outlined rose cuts. They have a pointed, dome shaped crown and a varying number of triangular shaped facets. DURABILITY OF FANCY SHAPES LILY CUT ASSCHER MANY VARIATIONS OF THE RECTANGULAR AND SQUARE STEP CUT EXIST IN THE TRADE TODAY. There are certain durability concerns with many fancy shapes. Since they are all asymmetrical shapes, quite often the stone is cut with some vulnerability to a diamond s natural grain lines. Often, the cutter is faced with misshapen rough and considering the goals to retain weight and remove imperfections and still produce a beautiful diamond, crown angles and other proportions may be compromised to finish the gem. A shallow crown (often seen in fancy cuts) is notoriously vulnerable to damage by chipping along the girdle edge just with daily wear. Any fancy cut diamond with a point be it the corners of a square or rectangular cut, i.e., end points of a marquise, heart or pear shape or even a long keel line at the bottom of the pavilion are extremely vulnerable to chipping and damage. These diamonds require special care when setting and protective prong styles (like a chevron ) are best. Just to name a few... These are all recently patented and/or trademarked branded fancy diamond cuts. The majority are squarish or rectangular shapes. Very few have met with success in the trade. Classic Asscher Princess Lily Original Radiant Cut Quadrillion Royal Asscher Asprey Corona Crisscut Cushette Czar Elara Escada Flanders Ideal Square Gabrielle J.C. Millennium Jubilant Crown Lady Cut Leo Lucere Lucida Millennial Sunrise PrinceCut Princess Plus Princette Regent Cut Royal Brilliant Royalcrest Starburst Trielle Tycoon Victorian Perhaps the most notorious cutting styles for chipped corners are princess cuts and baguettes. Very often these diamonds are damaged just by the act of setting them. LADYHEART IS ACTUALLY A COMBINATION OF HALF-MOON & PRINCESS CUT STYLES. BAGUETTE: TAPERED OR STRAIGHT SINGLE CUTS HALF-MOONS KITES TRAPEZOIDS TRILLIANTS Usually set as side or accent stones are: Baguettes which may be tapered or straight, Half-moons, Kite, Shield, Trapezoid, Triangular or other fancy cuts. FRENCH CUTS BRIOLETTES & BEAD CUTS ARE ENJOYING A REVIVAL

4 NATURAL FANCY COLOUR The Hope Diamond with its steely blue colour (45.52 carats!) is the world s most famous natural fancy colour diamond. Red diamonds are undoubtedly the rarest of coloured diamonds. Green and Blue coloured diamonds follow closely behind and are exceptionally rare. Following are the Purple, Pink and Violet colours then to orange and olive hues. Yellow, brown, champagne, gray and black diamonds are moderately rare and comparatively available. The beauty and the rarity of natural fancy coloured diamonds have spawned unprecedented desire and unparalleled prices. Diamonds come in a variety of colours. The majority of diamonds sold in the jewellery industry range from near colourless to very light yellow or brown. It s best to think of diamond colour in two categories: Colourless to near colourless; which have extraordinary ability to absorb all rays of light equally and fancy coloured diamonds which are in a class of their own. The colour in natural fancy coloured diamonds occurs because of certain elements like nitrogen or boron, were introduced in diamonds by nature during crystal formation. They are simply geological flukes. There are thousands of colourless diamonds compared to one fancy coloured diamond of desirable hue, and it is probably not high clarity. High clarity, although often preferred, is not a prerequisite for value. Each coloured diamond is different not only because of its natural body colour but also because of the way it is shaped and finally polished. Most fancy colour diamonds are cut into cushion or radiant shapes forms, which best bring out the depth of hue. The most skilled cutters shorten the optical light path through the diamond, creating the bright sparkle that is reflected from them. Cutting deeper pavilions and creating different facets may intensify colour. Fancy Coloured Natural Pink Diamonds Natural pink diamonds are some of the world's rarest and highly sought diamonds. It was not until 1979, when Australia discovered a small vein of pink diamonds that things really got exciting. Instead of being faint or light pink, these new diamonds are a variety of pink hues. The Argyle Diamond Mine in Australia is the world's foremost source of pink diamonds but even then only a handful is mined each year. Other countries of origin include Borneo, South Africa, Brazil and India. Most pink diamonds mined are faint to light coloured (pastel coloured) and the range of hues are like bubble gum, strawberry, raspberry, wine, baby, and cotton candy. High temperature and non-isotopic stress during diamond formation deforms the crystal lattice and displaces many carbon atoms from their normal positions. Hair like graining is also evident in some of them. Natural fancy coloured diamonds display colour in pale, distinct, deep or even vivid saturations. The fancy classification also includes completely unusual and rare lighter hues. Fancy Coloured Natural Yellow Diamonds Yellow is perhaps the most familiar diamond hue to the general public. Fancy yellow diamonds have four colour grades: Fancy Light Yellow, Fancy Yellow, Fancy Intense Yellow and Fancy Vivid Yellow - with increasing prices for higher intensity colours. Some of the yellows with higher intensity of colour (Fancy Vivid Yellows) are as rare as the pinks and blues and command unusually high prices. Although faint yellow in white diamonds is not desirable, fancy intense yellow is sought after. South Africa today is the main producer of these gems and yellow diamond rough also occurs in Brazil, and Russia. The best pure yellow or orangey-yellow will be called "fancy intense" or "fancy vivid" yellow on the GIA grading report, and are the most expensive. Slightly below these stones are the fancy yellows, which are more affordable but still quite yellow. Romantic names for yellow diamonds include canary, daffodil, lemon, autumn, golden, manila, chartreuse and saffron. Nitrogen in abundance is a major cause of yellow in diamonds. The secondary hues and colour modifiers for yellow diamonds include orange, green, brown, gray and olive. The rarity of colour affects prices. Pink diamonds gained great interest when Ben Affleck adorned Jennifer Lopez's hand with a large pink diamond! Demand for pinks noticeably increased.

5 WE DO NOT SELL TREATED FANCY COLOUR DIAMONDS NATURAL FANCY COLOUR Fancy Coloured Natural Champagne and Brown Diamonds Champagne Diamonds are Natural Colour Diamonds in beautiful Champagne tones, ranging from the pale soft Sherry tones to rich medium Champagne to deep dark Cognac. These surprisingly affordable diamonds provide a beautiful low cost alternative to pink, blue, gray, green or yellow diamonds. The interest in brown diamonds may be in its infancy. You can buy coffee coloured diamonds for much less than many white diamonds. Unlike other fancy coloured diamonds, the colour is valued for its paleness; very light browns are priced similar to G-I colours, light browns similar to J-M colours, and dark brown similar to S-Z colours. The colour is caused by atomic scale defects evident through graining (hair like growth lines) and twinning (intergrowth of crystals). The secondary hues and colour modifiers for brown diamonds include yellow, orange, pink, red and gray. These modifiers may enhance the beauty of brown diamonds. Brown diamond rough is mined in South Africa, Brazil, Australia and Russia. CHAMELEON DIAMONDS TEMPORARILY CHANGE COLOUR AFTER HAVING BEEN STORED IN DARKNESS OR WHEN HEATED. HUES ARE LIGHT TO DARK OLIVE TO LIGHT TO MEDIUM YELLOW. AFTER HOURS IN DARKNESS, EXPOSURE TO LIGHT GRADUALLY CHANGES THE YELLOW BACK TO OLIVE. THIS IS A REPEATABLE PROCESS. THE UNUSUAL SHAPE OF THE FANCY BLUE DIAMOND ALSO IS A SHALLOW CUT. SINCE FANCY COLOUR DIAMOND ROUGH IS THE MOST EXPENSIVE IN THE WORLD, CUT IS VERY OFTEN SACRIFICED FOR WEIGHT RETENTION. Champagne diamonds are graded according to a simpler C1-C7 scale created in the early 1990s Fancy Coloured Natural Red Diamonds Less than 20 stones have so far been certified as red diamonds by the G.I.A. Some red diamonds have fetched more than million dollars per carat and extremely few are known to exist. A 0.25 carat red oval sold a few years ago at Christie's for $326,800 per carat. Crystal lattice defects showing stress lamination during the formation of diamond causes the red colour. Their hues may be blood red, ruby, magenta, raspberry, rose, strawberry, cherry and tomato. The secondary hues and colour modifiers include pink, purple, brown, orange or gray. Red diamond rough is mined in Australia, Brazil and South Africa. Fancy Coloured Natural Blue Diamonds Also very rare and are most sought after by collectors. The colours range from faint to a very deep blue and may command higher prices than pink diamonds. Boron atoms cause the blue colour. An example of a diamond containing boron is the famous Hope diamond. Diamonds containing boron also exhibit unusual electrical properties and are semi-conductive in nature. Hydrogen is another impurity that, in high quantities, can cause grey or blue colouring in diamonds. The secondary hues and modifiers are: gray, green and violet. Rough blue diamonds are mined in South Africa, India and Australia. India was the main producer of blue diamonds from This was the source for the French Blue that later became the infamous carat Hope. Fancy Coloured Natural Green Diamonds Green diamonds with no other secondary hues or modifiers are of the rarest and depending on intensity and purity of colour, command astronomical prices. Most fancy green diamonds have gray, brown or yellow modifiers. Green colour in diamonds is caused by exposure to natural radiation in the Earth. At some point during its formation the diamond may have come in contact with radioactive material such as uranium ore. The presence of brown or green radiation stains on the surface is indicative if natural green colour. The green rough diamonds are mined in Brazil, South Africa, India, Australia, Congo, Ghana and Siberia. Fancy Coloured Natural Black Diamonds Diamonds with black as the primary dominant colour are unique. Blacks owe their colour to minute inclusions and random clustering throughout the stone rather than trace elements which produce colour in other fancy colour diamonds. They have a unique brilliance that seems to emanate from sheer darkness with the absorption of light by a pure black diamond being almost complete. Black diamonds were originally named "carbonados" by Brazilian independent miners, who discovered them in quantity in Natural black diamonds are difficult to cut and polish due to their varying degrees of hardness. This is one of the major reasons for enhancing the diamonds to black by either heating or irradiation. Most black diamonds on the market, especially those with low prices, are enhanced. Natural black diamonds are not to be confused with the quaint Alaska Black Diamond of the 1950s and 1960s. Those were actually faceted hematite stones marketed as diamonds. SPECIAL ORDER POSSIBILITIES: FOR NATURAL REDS, INTENSE PINKS, BLUES, GREENS AND OTHER UNUSUAL HUES SUCH AS VIOLET OR ORANGE THINK SLIM AND NONE. NATURAL FANCY YELLOWS VERY POSSIBLE IN LIGHT TO VIVID SATURATIONS; BLACKS, BROWNS & CHAMPAGNES ARE AVAILABLE.