ALLOY: The mixing of more than one metal in order to produce one of greater hardness, malleability and/or durability.
AMERICAN BRILLIANT CUT: A method of cutting diamonds to mathematical perfection to yield greatest brilliancy and fire. This is today the most popular cut for fine stones. It is employed in Europe as well as the United States Sometimes shortened to “American Cut.”
ART DECO: A style of design between 1910-1935., most importantly influenced by cubist geometry.
ART NOUVEU: A free-flowing curved revolutionary style of jewelry from the 1890’s until about 1910. Featuring delicate enamels and non-precious materials in the characteristic motifs of women with flowing long hair, bat, morning glories and dragonflies.
BAGUETTE: A step cut used for rectangular stones of a small size.
BEZEL: A metal rim which holds the stone in a ring, a cameo in its mounting or a crystal on a watch.
BRILLIANT CUT: The most beautiful form of cutting a diamond. It is also used for other clear stones. The standard brilliant has 58 facets, 33 in the crown and 25 in the base.
BROOCH: An ornamental piece of jewelry which has a pin back for affixing it to clothing or hats. Usually larger in scale than the ones referred to as “pins.”
CABOCHON: A stone cut in round oval shape in which the top is convex shaped (not faceted).
CALIBRE CUT: Small stones cut in the shape of squares, rectangles or oblongs used to embellish jewelry.
CAMEO: A layered stone in which a design is engraved on the top layer and the remainder is carved away to reveal the next layer, leaving the design in relief. Also done in shell, coral and lava.
CARAT: A unit of weight, by which the size of both uncut and cut diamonds is stated. A carat is equal to .200 grams. The newcomer to diamonds buying should be careful not to become overly influenced by carat size that he ignores, or fails to recognize the importance of such points as clarity, color and cut.
CHANNEL SETTING: A type of setting in which stones of the same size are held in place by a continuous strip of metal at the top and bottom literally creating a channel for the stones.
CLARITY GRADE: The quality of a diamond in terms of its clearness or absence/presence of imperfections, expressed according to standard scale.
CLAW SETTING: A style of ring settings in which the stone is held by a series of vertically projecting prongs.
COLOR GRADE: The color quality of a diamond, expressed according to a scale of letters representing different grades of color (see “Grading Section”). Crystal clear, or absolute lack of coloration, is the most desirable; these are often referred to as “white” diamonds.
CROSS-OVER: A style of ring, bracelet or brooch in which the stone set decorative portions overlap and lie alongside each other.
CULTERED PEARL: A type of pearl induced and stimulated by man to grow inside a mollusk.
CUSHION CUT: A square or rectangular shape with rounded corners. Also called “antique cut.”
EMERALD CUT: A style of rectangular or square cut, featuring steps of elongated facets.
ENGRAVED: To cut into, to form a pattern or design either by hand or machine.
FANCY DIAMOND: A colored diamond, whose color is intense enough to be a plus rather than a minus. Faintly colored stones are invariably worth less than pure colorless ones.
FILAGREE: Ornamental open work executed in fine gold or silver wire.
FLAW: A blemish or imperfection, either on the surface of a diamond or the interior. This may be in the form of a scratch, feathering, carbon sports, etc. Bad color is not technically considered a flaw; nor is anything relating to the proportioning or cut.
FOUR C’s: Common trade term to collectively describe the major considerations in a diamond’s value: clarity, color, carat, and cut.
GERMAN SILVER: A silver-white alloy composed mainly of copper, zinc, and nickel called silver but containing none.
GOLD FILLED: Gold filled articles are similar to plated: they have an exterior of gold and a core of base metal, usually copper. The difference is in the method of application. Plated objects are shaped and then bullion-coated by electroplating in which the soft gold takes the object’s form. Gold filled merchandise is made from sheets of metal to which the outer covering of gold has been applied before the object is shaped.
GOLD: Pure 24K gold is yellow in color. It is very soft and not acceptable for use in articles to wear, unless alloyed with harder metal. The choice of alloy metals determines the color of the gold.
GUNMETAL: An alloy of 90 % copper and 10% tin that was very popular in the 1890’s.
GYPSY SETTING: A type of setting in which the stone is set down flush in the mounting.
HALLMARK: A group of markings used on silver and gold in England since 1300 to designate the fineness of the metal, the town in which it was assayed, and the name of the maker.
IMPERFECTION: A flaw or blemish, caused by nature or man, which may be on the outer surface or the stones’ interior. Poor color or unskilled cut are not classified as imperfections, though they do, of course, play a role in value determination.
JEWEL: Synthetic or semi-precious stones used for bearings in watches and precision clocks.
KARAT: The method by which fineness of gold is expressed. Pure unalloyed gold is 24 karat. As alloy metal is added (usually copper, for strength or to reduce the price), the karat value declines: 22K, 20K, 18K and so on. The lowest grade of gold to carry a karat marking is 10K, or, in Great Britain, 9K. Most gold coins are 20K or 21K. Jewelry is commonly made of 9K to 18K. The word “karat” derives from the carob bean, used as a measure of weight in the ancient world. When spelled “carat” refers to the weight of a precious gem and has nothing to do with the fineness of a metal in the United States.
MARQUISE CUT: A cut for diamonds in which the stone is brilliantly faceted and then shaped like an elongated almond or tear-drop with pointed ends.
MOSAIC: A piece of jewelry in which the pattern is formed by the inlaying of various colored stones or glass. Two types of mosaic work are Roman and Florentine.
NICKEL SILVER: An alloy of nickel, copper, and zinc; usually 65 percent copper, 5-25 percent nickel and 10-30 percent zinc, containing no silver.
OLD EUROPEAN CUT: Style of cutting popular in the 19th century, direct predecessor to the modern Round Brilliant. Old European cuts have a smaller table than the Round Brilliant and heavier crown; overall depth is somewhat greater. Also called “old mine.”
OLD MINE CUT: In general, a diamond cut into an early style of round cut, prior to the Modern Round Brilliant cut method of mathematical calculation, is referred to as an “old mine cut”. Apparently it was mistakenly believed that diamonds were once cut at the mines before wholesaling.
PAVE SETTING: A style of setting in which the stones are set as close together as possible, presenting a cobblestone effect.
PENNYWEIGHT (DWT): A unit in troy weight equal to twenty-four grams or one-twentieth of an ounce.
PLATING: The covering of base metal articles with a layer of gold or silver, which may be various thicknesses and grades. Presence of plating may be discovered by filing and using nitric acid, or subjecting the item to specific gravity testing.
PRECIOUS METAL: The three primary previous metals are gold, silver and platinum. All others (except derivatives of these three) are known technically as “base metal”. Of course, the preciousness of precious metals varies, as does the baseness of base metals.
PURITY: The proportion of precious metal vs. base metal in an object. A purity of .900 would mean a content of 90% precious metal and 10% base metal alloy, or a ratio of 9 to
ROSE CUT: Method of faceting stones with many small and usually not precision cuts.
SPEED PEARL: A small pearl weighing less than ¼ grain.
SINGLE CUT: Simple style of cut employed on small stones, usually those intended to be used in mounting in conjunction with a large central stone. Single cuts are circular at the girdle.
SOLID: When an object is referred to as a solid bullion, this means it is not plated or filled but that its interior composition is identical to its exterior. Bullion can be either heavily or lightly alloyed. “Solid gold” is not necessarily 24K.
STERLING: The minimum standard of purity of fineness of English silver, 925 parts pure silver to 1000 parts.
SYNTHETIC: A man-made material with the same physical, chemical and optical properties as the natural. Not to be confused with imitation.
TABLE: The uppermost plane surface of a cut diamond. Like the other plane surfaces, the table is also a facet.
TROY WEIGHT: The system of weights commonly used in England and the United States for gold and silver. One pound equals 12 ounces. 1 ounce equals 20 pennyweights (dwt.) and 1 pennyweight equals 24 grains (gr.).
VERMEIL: Gilded silver.
WHITE GOLD: 24 karat yellow gold alloyed with nickel to make 10, 14 or 18 karat white gold.
WHITE: Misleading term meaning colorless or clear. Derives probably from the fact that in olden time white was not recognized as a color but as the absences of color. A really white diamond, smoky or cloudy, is not nearly as desirable as clean.
ZIRCONIA, CUBIC: Synthetic material from which imitation diamonds are made. Extremely difficult to distinguish from a natural diamond, except for a very experienced appraiser or through use of special equipment, such as the Diamond Probe. It has a greater hardness than many other synthetics, but its hardness is not equal to diamonds.