Gemstone Setting Types Carré, Pronged & Tension Settings

Closed and Open Settings There are two basic types of gemstone settings: open settings and closed settings. Open settings are any type of setting that allows light to enter through the bottom of a faceted or transparent cabochon gemstone. In a "closed setting" light can only enter the stone from the top. This type of setting is appropriate for opaque cabochon-cut stones and highly refractive faceted stones where light can enter through the crown and table of the stone and be reflected back to the observer from within. Open Gem Setting Types Prong Settings Within the category of "open settings" or "à jour settings" there are several variations. The most common variety for faceted gemstones is a prong setting (below, left), with either 3 or 4 prongs that hold the stone in place. This type of setting exposes the maximum amount of light to the sides and bottom (pavilion). Gemstone Carré Settings & Prong Settings Carré Settings A Carré setting is where the stone is seated directly over a light well (above, right), and the stone is set by raising (hammering) four "spurs" with a "graver" tool. Tension Settings A "tension setting" uses the metal's natural tendency to "spring" back to its original position to hold the stone in place. The metal is spread apart, and the girdle of the stone is seated into small grooves in the inside surface of the metal. This type of setting requires special alloys of metal that are strong enough to create and withstand the necessary pressure to hold the stone firmly. Tension settings are only appropriate for very hard stones (Hardness of 9 to 10: diamond, ruby, sapphire, cz or moissanite) as the setting can exert up to 12,000 lbs. of pressure per square inch on the stone's girdle. The tension-setting was developed in the 1960s by Professor Friedrich Becker of Niessing in Vreden, Germany. Metallurgist Steven Kretchmer of New York (ring at top, center) holds several recent patents for his advanced techniques in heat-treating alloys to increase strength and elasticity. Gemstone Tension Settings & Frustum Settings Frustum Settings A Frustum, or "Hollow Cone" setting is a conical or tapered setting constructed from sheet metal. The stone's pavilion rests against the inside of the cone and the outer edge of the cone's lip is bet over the girdle to secure the stone. A frustum setting can be open or closed. Closed Gem Setting Types Variations of the closed setting are the "bezel (gypsy) setting, channel setting, cluster setting, Kundan setting, frustum setting, Pavé, and the seamless tube setting. Bezel Settings The oldest and most basic gemstone setting is the "Bezel", derived from the French word "Biseau" meaning chamfered. Used primarily to set cabochons, a vertical strip of metal is formed to encircle the stone, then soldered to a metal base. The stone is secured by pushing and bending the bezel towards the stone using a burnishing tool. Gemstone Bezel Settings & Channel Settings Channel Settings Channel settings are primarily used to set faceted gemstones that are straight-sided, or quadrilateral in shape (baguette or princess cut). The stones are aligned in a channel, sitting girdle-to-girdle. step-cut stones can rest on a track giving a "keystone" effect. Matching stones that are cut to a uniform size for use in channel settings are called "calibré-cut," as in "Eternity Rings." Gemstone Channel Settings Pavé Settings A Pavé Setting is a tight grouping of identically sized stones laid across a flat, or convex surface, from the French word for "paved." The stones are held in place using three to six raised beads per stone.

Old European Diamond Cuts Point, Old eight, Old Mine Cut

Point Cut - early 1300s The "Point Cut" (below left) is one of the first symmetrically faceted diamond cuts. The Point Cut design is dictated by the natural shape of an octahedral rough diamond. The "Table Cut" (below, right) was created by cutting off some of the top half of the Point Cut's octahedron to create a table. Gemstone Cutting History - Point Cut Single Cut - late 1300s Invented in the late 14th century, the "Old Single Cut" (aka Old Eight Cut) diamond has the addition of corner facets to create an octagonal girdle, an octagonal table, eight bezel or crown facets, and eight pavilion facets. The Single Cut may or may not have a culet at the bottom. Gemstone Cutting History - Single Cut Rose & Briolette Cut- 1500s Invented in the mid 16th century, the Rose Cut is also known by the the Antwerp rose, Crowned Rose Cut, Dutch Cut, and the Full Holland Cut. The Rose cut can form a single hemisphere for a total of 24 facets or it can be two back-to-back hemispheres (Double Dutch Rose) forming a total of 48 facets. The "Senaille Cut" is a Rose cut with irregular or non-symmetrical faceting. The "Briolette Cut" is a modified Double Dutch Rose cut with one of the hemispheres being elongated. Gemstone Cutting History - Rose Cut & Briolette Old Mine Cut - 1700s The "old mine" cut is the earliest form of the "brilliant cut" diamond. Also called the "cushion cut", it has a cushioned or rounded girdle shape. This Old Mine cut is basically square with gently rounded corners and "brilliant" style facets. The crown is typically tall, resulting in a smaller table. The culet is usually large enough to be visible when viewed through the table. Gemstone Cutting History - Old Mine Cut Old European Cut - 1800s The "Old European" cut was the forerunner of the modern Brilliant Cut. The Old European diamond cut has a very small table, a heavy crown, and very tall overall depth. Like the modern round brilliant, the old European diamond has a circular girdle. Gemstone Cutting History - Old European Cut The Modern Round Brilliant Cut - 1900s The "Modern Round Brilliant Cut" (below) was developed by Belgian diamond-cutter Marcel Tolkowsky in 1919. This cut is also known as the "Tolkowsky Cut" and "Tolkowsky Brilliant." Even with modern techniques, the cutting and polishing of a diamonds resulted in a loss of as much as 50% of the stone's total weight. The round brilliant cut was a partial solution to this problem. Gemstone Cutting History - The Modern Round Brilliant Cut As with its predecessor the "Point Cut" over 600 years earlier, the Modern Round Brilliant cut is beneficial when the crystal is an octahedron (diagram above), as two stones can be cut from one crystal with a minimum amount of waste. Eight Cut & Swiss Cut The "Eight Cut" is primarily used for small stones when a brilliant cut would be impractical. The eight cut is similar to the "Single Cut" in that there are eight four-sided trapezoidal facets at the crown, eight facets at the pavilion, and an octagon-shaped table for a total of 17 facets (18 if a culet is used). Gemstone Cutting History - Eight Cut A "Swiss Cut" is a compromise between an eight cut and a Brilliant Cut, with a total of 33 facets (34 if a culet is used); 16 isosceles triangle facets on the crown and 16 facets on the pavilion.

Fancy Gem Cuts Glyptic & Fantasy Cuts (Fantasieschliffe)

Fancy Cuts Asymmetrical crystals such as macles are usually unsuitable for symmetrical cuts such as the Round Brilliant, and lend themselves to a "Fancy Cut" style. These fancy cuts can follow the best attributes of the rough stone while eliminating or avoiding cleavage planes, internal flaws, and inclusions. Popular fancy cuts include the "Baguette" (bread loaf), "Marquise" or "Navette" (little boat), "Princess Cut" aka Square Brilliant Cut, "Heart", "Briolette" (a form of Rose cut), Pear (teardrop), and the Trillion which is triangular in shape. Fantasy Gem Cuts Concave Faceting Concave faceting cuts are a relatively new trend on the gem-cutting scene (amethyst - above, left). Invented by Doug Hoffman in the early 1990s, the technique was perfected by American gem-cutter Richard Homer. The unique conical-shaped faceting creates a high amount of brilliance by refracting and dispersing more incident light than a conventional facet cut. Cross Cuts, French Cuts, & Step Cuts An emerald cut, as shown in the diagram at the top of the page (upper, left), is a modified step cut with the corners cut at a diagonal angle. With a step-cut, the crown, pavilion, and the table are all cut in rectangular facets. This type of step-cut does not produce much brilliance, but it is an effective cut for showcasing a stone's color attributes (as with emeralds). Cross Cut, French Cut, & Step Cut Fancy Gem Cuts Popular variations of the step-cut are the Scissor-Cut or Cross-Cut, Baguette Cut, and the French-Cut (above, center). These cuts add slightly more brilliance to the stone a dark stone, and are good for concealing internal flaws. The french cut is also used on very small stones where a brilliant cut would not be practical. Navette Cut The "navette-cut" or marquise cut (shown in simplified form - above, center) is a popular choice for colored stones such as topaz, citrine, Amethyst, and Aquamarine. The navette cut may have been the creation of King Louis XV of France, who was so taken with the delicate shape of his courtesan's (Marchioness Madame de Pompadour, below, right) mouth that he commissioned his court jeweler to create a gem cut in its likeness. Isosceles Triangle Cut Citrine & Madame de Pompadour Composit Gemstone Cuts Composit gemstones are created by bonding two or more materials together to form one gemstone. When the final gem is made of two different materials it is called a "doublet," and when made with three, a "triplet." Common doublet or triplet gemstones are Emerald and Opal, usually combined with quartz or glass. Compositing is used to improve color and add durability. In faceted composite stones, the crown would be the natural material. So far, the consistent theme in all of these fancy cuts is their symmetry. As a fancy gem cut takes on a more asymmetrical shape, such as the Isosceles Triangle Cut citrine above (left, with trillion diamond), it would be labled as a "fantasy cut." Fantasy Cuts (Fantasieschliffe) Gemstone Cutting History - Bernd Munsteiner There is also a new addition to the gem cutting universe: the "Fantasy Cut" or Fantasieschliffe. There is probably no person who is more famous at this relatively new art form than the German stone cutter Bernd Munsteiner. The Munsteiner family (Bernd, Tom and Jutta) at Atelier Munsteiner have been pushing the boundaries of stone cutting to their limits with their endlessly imaginative shapes and forms. Gemstone Cutting History - Munsteiner Fantasy Cuts Fantasieschliffe A somewhat softer, more organic variation of the Munsteiner family's Fantasieschliffe cuts are the "Glyptic Illusions" sculptured gemstones cut from Bart Curren. Bart, also known for his digital photography of gemstones, lives and works in Washington State, USA. Although modern saws, grinders and polishers are used to create these fantasy cuts, this type of stone cutting brings back the lost art of "hand-cut" craftsmanship. Although the only limit to the design is the cutter's imagination, an intimate knowledge of a mineral's cleavage and optical or refractive properties in necessary to get the most out of a stone's natural beauty.

Diamonds Proprietary 'Signature' Diamond Cuts

Notable Patented Diamond Cuts Patented Diamond Cuts - Asscher Cut Asscher Cut The Asscher Cut was developed by Abraham and Joseph Asscher of the Royal Asscher Diamond Company of Amsterdam in 1902. Popular in Art Deco jewelry, the Asscher diamond cut has a squarish octagonal shape with a step cut, cut corners and a small table. The cut has a deep pavilion and a high crown, and the culet is square. The Asscher brothers cut the famous 3,106 carat Cullinan Diamond into eleven gem stones, with the two largest stones, the Cullinan 1 and 2 being set into the crown and sceptre of the British Crown Jewels. www.asscher.nl Patented Diamond Cuts - Barion Cut Barion Cut The Barion Square Cut (aka Barion Square Cushion Cut) was invented by Basil Watermeyer of South Africa in 1971 and was the forerunner to the princess cut. The name "Barion" was never trademarked and the patent has expired. The Barion Square Cut has 4-fold mirror-image symmetry, and a total of 81 facets (not including 16 girdle facets). Patented Diamond Cuts - Barocut Barocut The Barocut® diamond cut is a patented, modified rectangular (baguette) cut that was developed by Baroka Creations, Inc. of New York in 2000. The Barocut is also called a "Two Heart Diamond" due to the illusion of two mirrored hearts meeting at the culet. A Barocut diamond has a total of 77 facets, or to increase light-dispersion, 81 facets on the cut corner version. Barocut stones are also asold in tapered shapes. Barocut diamonds are promoted and sold exclusively through Baroka Creations' catalog or company website. The Barocut is available in sizes from 20 points to 3 carats, and in all diamond colors and clarity grades. www.baroka.com Patented Diamond Cuts - Context Cut Context Cut The Context Cut is a square cut that was developed by Dr. Ulrich Freiesleben of Germany in the early 1980s then patented and trademarked in 1997. The Context Cut consists of two back-to-back pyramids (an octahedron), forming a square shape when viewed from the top. The Context Cut follows a rough diamond crystal's natural octahedral shape, with star-shaped cross facets cut diagonally into the pavilion. The cut has a total of 8 facets plus a girdle. The Context Cut design was based on an earlier patented design by Bernd Munsteiner from the early 1960s. The cutting process requires a high-quality rough, and creates a high amount of waste, adding up to 50% to the cost when compared to a Round Brilliant cut diamond. The Context Cut is used to cut colored gemstones by Julius Petsch of Idar-Oberstein, Germany. www.freiesleben.de Patented Diamond Cuts - Eternal Cut Eternal Cut The Eternal Cut diamond was designed and patented by master Israeli diamond cutter, Gabi Tolkowsky, nephew to the inventor of the Modern Round Brilliant cut, Marce Tolkowsky. It is sold exclusively through the 270 year old firm of Garrard & Company in London. In 1998, Garrard & Co. merged with the jewelry firm Asprey, to become Asprey & Garrard, parting ways in 2002 to again become Garrard. The Eternal Cut has a total of 81 facets, 23 more than a modern Round Brilliant cut, creating a unique 'flower petal' pattern surrounding the cutlet, and a 'softer' briliance than a traditional round brilliant cut. The Eternal Cut is being sold exclusively at Garrard's main London store and Harvey Nichols stores in Great Britain. www.garrard.com Patented Diamond Cuts - Flanders Brilliant Cut Flanders Brilliant Cut The Flanders Brilliant Cut (aka Fire Brilliant) is a modified Radiant or Princess cut with truncated corners that form an octagon with brilliant faceting. The Flanders Brilliant has 33 crown facets and 28 pavilion facets for a total of 61 facets. The Flanders Fire-Brilliant was developed by Flanders Cut International of Antwerp in 1983, and the cut was named after the Flanders region of Belgium (Antwerp) where the cut was first preformed in 1987. The cut is distributed by the National Diamond Syndicate (NDS) of Chicago. www.flanders-cuts.com www.nationaldiamond.com Patented Diamond Cuts - Flower Cut Flower Cut The 'Flower Cut' series was created by Gabi Tolkowsky in 1986, who was commissioned by De Beers to create new cuts as a way of marketing unusual, off-color stones. The Flower Cut is actually a series of five fancy cut shapes: the Dahlia, Fire-Rose, Marigold, Sunflower and Zinnia cut. The Flower Cuts employ unconventional cutting angles and dimensions, designed to maximize the brilliance and color of diamonds while increasing their yield. The Flower Cuts were never patented or trademarked by De Beers in order to increase their popularity and use. The Dahlia is a 12 sided oval shape with 63 facets. The Fire-Rose is a hexagonal shape designed to produce higher yields. The Marigold is an octagon shape with 73 facets, that is suited to a relatively flat rough. The Sunflower has 43 facets in unusual, angular shapes. The Zinnia is a round fancy shape with 73 facets, 48 of which are clustered around the culet to increase fire. Patented Diamond Cuts - Gabrielle Diamond Cut The Gabrielle Diamond The Gabrielle® Cut is a modified brilliant cut (triple brilliant cut) that was created by DeBeers desinger/consultant Gabriel Tolkowsky in 2000. Unveiled at the Las Vegas Gem Show in 2001, the Gabrielle has a total of 105 facets, which is 47 more than a traditional 'Tolkowsky' round brilliant cut, adding greater brilliance and fire than standard brilliant cuts. Other than the traditional round brilliant shape, the Gabrielle Cut is available in carre, emerald, heart, marquise, oval, and pear shapes. www.gabriellediamonds.com Patented Diamond Cuts - Leo Cut Leo Cut The Leo® Diamond, (aka Leo Schachter Diamond), is a patented symmetrical round cut created by Leo Schachter Diamonds, LLC. The Leo diamond cut has a total of 66 facets, 8 more facets than the Round Brilliant cut's 58, maximizing the amount of light returned back as scintillation. The Leo diamond cut is the first to be certified for fire and brilliance as measured by a 'BrillianceScope,' and each diamond comes with a "Return of Light Certificate." The Leo Diamond is marketed through the Kay Jeweler chain. www.diamondaires.com Patented Diamond Cuts - Lucida Cut Lucida Cut The Lucida (TM) Cut is a patented diamond cut that was created by Tiffany & Company in 1999. The Lucida diamond cut is a modified square or rectangular (Marquise) cut with truncated corners, a high-step crown (similar to the Asscher Cut), small table, brilliant-style faceted pavilion (similar to a Cushion Cut), and a total of has 50 facets. The Lucida is sold exclusively through Tiffany's retail chain. The Lucida diamond cut is marketed as a wedding cut, sold in solitaire engagement/wedding bands, eternity bands, and three-stone rings. www.tiffany.com Patented Diamond Cuts - Quadrillion Cut Quadrillion Cut The Quadrillion® Cut (aka Squarillion Cut) is a modified square Princess Cut that was developed by Israel Itzkowitz and Betzalel Ambar in the late 1970s, and was patented and trademarked by Bez Ambar Jewelers of Los Angeles in 1980. Prior to the Quadrillion, square shaped diamonds were step-cut limiting their brilliance. The Quadrillion was the result of three years of optical research to create a square diamond cut that can claim a similar brilliance to a round diamond. There are a total of 49 facets. Bez Ambar Patented Diamond Cuts - Radiant Cut Radiant Cut The Radiant Cut is a modified emerald shape that was developed, patented and trademarked by Henry Grossbard of the Radiant Cut Diamond Company (RCDC) in 1977. It was the first emerald shaped diamond cut to have brilliance and fire similar to that of a round brilliant diamond. Upon the expiration of the patent, the Radiant Cut became a fully accepted diamond shape in the jewelry business. RCDC launched the 'Original Radiant Cut' diamond brand In 2002, and all Original Radiant Cut diamonds weigh at least 0.70 carats and come with a GIA Certificate and an "Original Radiant Cut Diamond Certificate" guarantying that the stone meets the ideal proportions as designed by Henry Grossbard. There are 25 crown facets and 36 pavilion facets for a total of 61 facets (not including 8 girdle facets). The pavilion is similar to a Barion cut, and the table is a bowed out rectangle. www.radiantcut.com Patented Diamond Cuts - Starburst Cut Starburst Cut The Starburst Cut was patented and trademarked by the Louis Glick Diamond Corp. of New York in 1978. The Starburst cut was created to bring out the highest amount of color to fancy yellow diamonds. The crown of the Starburst Cut is similar to that of the radiant cut, but the pavilion is completely different. There are 49 crown facets and 40 pavilion facets, for a total of 89 kite and star shaped facets. The Starburst cut is especially suitable for a octahedral rough, with weight losses in the fifty percent range. The starburst faceting pattern is designed to focus color near the top of a stone, making the hue of fancy yellow diamonds more intense. Starburst Cuts are mounted and sold directly through Cartier, Harry Winston, Nieman Marcus and Tiffany. www.louisglick.com Patented Diamond Cuts - Trilliant Cut Trilliant Cut The Trilliant Cut (aka Trielle, Trillian, Trillion) is a triangular cut designed and trademarked by the Henry Meyer Diamond Company of New York in 1962. The Trilliant trademark has since lapsed, and the Trilliant is now a generic term for a triangular brilliant cut. The Trilliant has the Schoenflies point group symmetry of a round brilliant, reworked into the shape of a trillion (triangle). The Trilliant Cut has a total of 31 facets. The pavilion has two differently sized sets triangular facets with a large triangular table. There are two variations of this cut: the Curved cut used for solitary stones, and Uncurved cut used for accent stones. The Trilliant cut gives a high brilliance, fire, and scintillation when cut to the correct proportions.

Cutting a Rough Stone Cutting a raw stone into a faceted and polished gemstone is a multi-step process. Each step is critical to the final outcome. The steps are: * Marking * Cleaving * Sawing * Girdling (Bruting) * Faceting (Cross Working) * Brillianteering Marking: A rough stone is marked prior to cleaving or sawing to determine the direction of the grain or "cleavage", eliminate waste, and bypass inclusions or imperfections. The natural shape of the rough stone will also be a major factor in deciding how to cut the stone. Cleaving: Cleaving refers to splitting a stone along its grain by striking it. A rough stone is cleaved if there are conspicuous defects and/or inclusions which would prevent it from being made into a single gemstone. Sawing: The rough stone is cut to a shape that approximates the shape of the finished cut stone but without the facets. Girdling: The rough is placed in a chuck on a lathe. While the rough stone rotates on the lathe, a second diamond mounted on a dop is pressed against it, rounding the rough diamond into a conical shape. This step is also referred to as rounding or bruting. Faceting: The cutting and polishing of each facet is accomplished by attaching the stone to a dop stick and pressing it against a revolving lap (see "Facetron" below). During this faceting stage the angles of each facet must be cut in order to maintain symmetry and produce maximum brilliance. Brillianteering: If the primary Faceting or "Cross-Working" is done by a separate craftsman, the final 40 facets of a round brilliant cut diamond's 58 facets will be cut by a Brillianteer. Gemstone Color Evaluation For evaluating the color of a gemstone, it is crucial that the identical light source, intensity, and color temperature is used every time. A "Gem Light Box" gives off a stable 4800 to 5200 Kelvin degrees (natural, indirect sunlight). Some light boxes have a UV component to the light for grading pearls or colored stones (Fraunhofer Solar Spectrum Chart, below). Fraunhofer Spectrum Chart Diamond Faceting design & Rough Evaluation Diamond Manufacturing factories use sophisticated electronic equipment for cutting and evaluating cut diamonds. Using the latest hardware and software to create highly accurate 3D models, these scanners measure the angle of inclination of a facet and its azimuth, allowing the operator to pre-visualize a 3D model of the cut stone. HeliumPolish Scanners are used for Round Brilliant Cuts as well as Fancy cuts. A device called a Pacor Oxygen Scanner can be used for optimizing rough stones based on purity to evaluate inclusion removal or reorientation. Gemstone Cutting History - HeliumPolish Scanner Diamond Bruting Girdling or bruting the rough is a critical phase where the stone is placed on a lathe while a second diamond mounted on a dop is pressed against it, rounding the rough diamond into a conical shape. AutoBruters use the latest technology to preform "non-contact" measuring to overcome inherent problems in the rounding process. using live video and image analyzing software, potential out-of-roundness and any deviations from the desired dimensions and a computer will guide the machine to take necessary actions by slowing the bruting speed or pressure. Gemstone Cutting History - HeliumPolish Scanner Gem Analyzers An "IdealScope" or "H & A Viewer" (below, center) uses a 10x lens with a pink/red reflector positioned in front of the diamond under a central viewing hole, allowing the viewer to see how much of the red/pink light refracts back from the diamond. The resulting pattern will be a good indicator of faceting proportion and symmetry. Gemstone Cutting History - HeliumPolish Scanner For performing Cut Analysis on a finished stone, a Dia-Analyser (above, right) uses a camera to take photographs of the finished diamond while it is being rotated. The computer's software will digitize and the analyze the data to quantify all of the cut parameters. Lapidary & Gem Cutting Equipment Gemstone Cutting History - Scintillator & Facetron The machine to the upper left (Poly-Metric Scintillator 88 Digital) and to the upper right (Facetron) are semi-automated faceting machines. Machines such as these have taken some the guess-work out of stone cutting, but a skilled craftsman must cut a rough stone to its optimal size and and take ito account any inclusions or imperfections that must be eliminated in the cutting process. By examining the rough stone under a Loupe, the gem-cutter will decide which type of cut will show the stone's best attributes. Cabochon Grinder Gemstone Cutting History - Cabochon Machine Facetron and Lapidary Gem Saw The Facitron (left) and Scintillator (upper right) are water-cooled faceting machines designed to make cuts at precise angles by mathematically plotting out to depth and degree of a given facet. The rough gemstone is held by a chuck called a "Dop" "Dop Stick" or "Dop Chuck" and ground against a grinding plate called a "Lap". The rough stone is held to the dop with hot-wax glue. By adjusting a dial indicator (protractor) the gem-cutter can control the degree of cutting angle to a tolerance measured in hundredths of an inch. Gemstone Cutting History - Facetron & Gem Saw The image at center/bottom is a rough gemstone attached to a dop stick. The image to the right is a combination lapidary gemstone saw (slab saw) and grinder.

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