Alloy - A mixture of two or more metals combined to give the metal greater strength.
Amber - The fossilized resin of prehistoric pine trees which ranges in color from golden to orange-red.
Amethyst - A variety of quartz found in deep purple to a bluish-violet color.
Annealing - The process of heating metal and then cooling it to render the metal more pliable
Antiquing – A process of darkening the recessed area of gold or silver jewelry to enhance the visibility of the engraving, thus lending the look of age or natural patination. Platinum cannot be antiqued
Aquamarine - A form of beryl found in pale green blue to clear blue colors
Asterism - Common term used in gemology which refers a kind of special optic phenomenon that has been seen in several gems. Gems, which show an illuminated star, just bellow the surface of crystal are called star gems. The most popular star gems are star ruby and star sapphire. Other gems, which also possess the special optic phenomenon "asterism", are rose quartz, garnet, spinel, chrysoberyl and diopside.
Aventurescence - Is an optical reflectance effect seen in certain gems. The effect amounts to a metallic glitter, arising from minute, preferentially oriented mineral platelets within the material. These platelets are so numerous that they also influence the material's body color
Bail – The connector at the top of a pendant, enabling the pendant to hang from a chain or jumpring
Baguette – A small, four-sided step cut that’s rectangular, square, or tapered.
Bangle - Non-flexible bracelet
Base Metal – Any combination of alloys of non-precious metals
Bezel - Gemstone setting where a strip or collar of metal encircles the gemstone to hold it in place instead of prongs
Blemish – Clarity characteristic that’s confined to the surface of a polished gemstone.
Blue Topaz – A topaz that is light brown or colorless when mined but turns a vivid blue when exposed to heat.
Brass – An alloy of copper and zinc
Brilliant Cut – A cutting style in which triangular and kite-shaped facets radiate from a gem’s center toward its girdle.
Brilliance – The brightness created by the combination of al the white light reflections from the surface and the inside of a polished diamond.
Briolette – A teardrop shaped stone faceted with triangular or rectangular facets, sometimes pierced at the top, also known as ‘drop-cup’
Cabochon – Stone with a smooth carved surface, domed and unfaceted with a flat base
Carat – The international unit of measurement for gem weight. One carat equals 1/5 of a gram (0.200g).
Carnelian – A translucent red or orange variety of chalcedony, sometimes banded red and orange like an agate. Once believed to benefit the wearer’s health and love life.
Casting – Process of forming an object by pouring a molten or liquid substance into a mould until it solidifies and takes on the impression of the mould
Channel Setting – A row of stones of the same dimension, fitted into a metal channel
Choker – A close fitting necklace worn tight around the neck like a collar
Citrine – A variety of quartz found in a range of colors from light yellow to red-orange to almost brown
Clarity Characteristics – The collective term for inclusions and blemishes
Conflict Diamonds – Rough diamonds used by rebel movements or their allies to finance conflict aimed at undermining legitimate governments.
Crown – Part of a cut gemstone above the girdle
Cubic Zarconia – Man made gems which appear very much like diamonds, yet do not have the same intrinsic properties such as hardness. CZ’s are mass produced and much less expensive than natural diamonds.
Culet – The pointed bottom of the pavilion part of a gemstone, sometimes polished with a tiny facet, sometimes pointed with no facet
Cultured Pearl – An oyster or mollusk is artificially “seeded” with a tiny grain of sand. The mollusk then excretes a coating to protect itself from the irritant. Several layers are accreted, creating a real pearl.
Claddagh - An Irish design (as on a ring or other piece of jewelry) of two hands holding a crowned heart that symbolizes friendship, loyalty, and love
Clarity Characteristic – Internal or external feature of a gemstone that helps determine its quality and establish its identity.
Cleavage – The splitting or tendency of a crystal to split along definite crystalline planes to produce smooth surfaces
Cushion Cut – A square or rectangular stone that has rounded corners, also called an ‘antique cut.’
Cut – A description of the type of facet of a gem
Doublet – A gemstone that is composed of two parts; usually valuable gemstone material in combination with other, less expensive material. This is not a natural occurrence, but rather a man-made fabrication where two pieces of material are glued together to form a sort a composite or "gemstone sandwich". Usually the crown (top of the stone) is natural gemstone material while the pavilion (bottom) is composed of an inexpensive material such as synthetic sapphire, quartz or glass.
Electroplating – A method in which an electric current deposits a layer of metal on an object (for example; gold over a base metal)
Emerald Cut – Rectangular shaped stone with mitered corners which is elongated and octagonal
Enamel – Process of fusing powdered colored glass to a surface by means of high heat
Engraving – A technique in which metal is cut away with a tool known as a ‘graver’ to form a design; done by either hand or machine
Etching – Removal of part of a metal surface by acid for a decorative effect
Eternity Ring – A ring that has diamonds, or other gemstones, that go all the way around the band
Facet – A flat surface ground or cut and polished on athe surface of a gemstone
Fancy-Colored Diamonds – Diamonds that exhibit yellow or brown color beyond the Z range, or that exhibit any other color.
Fancy Cut – Any gemstone shape other than round.
Feather – A trade term for any break in a diamond.
Filigree – Wire twisted into patterns, usually god or silver, may be soldered to a sheet of metal or twisted to form an openwork pattern
Fluorescence – Emission of visible light by a material when it’e exposed to ultraviolet radiation.
Fracture Filling – Treatment that involoves injecting a molten glass substance into a diamond’s surface-reaching feather or laser drill-holes.
Gold Filled – Jewelry that is gold filled employs a process in which gold is bonded to a base metal alloy such as nickle or brass. Commonly, the amount of gold used must make up at least 5% of the total weight and all exterior portions are gold.
Gold Plated – Jewelry that is gold plated employs a base metal which is then electroplated with gold. Usually a steel or brass item dipped into a bath of electrplating solution that deposits a thin layer of gold on the jewelry. The gold layer is less than gold filled, quite thin and will wear off faster than gold-filled.
High Presure, High Temperature (HPHT) – Diamond synthesis method that mimics the pressure and temperature conditions that lead to natural diamond formation
Inclusion – A Characteristic inside a gemstone, or a characteristic reaching the gemstone’s surface from inside. Examples are fractures, breaks, other crystals, gas bubbles, hollow tubes, or even insects.
Ingot – A precious metal formed into a bar or brick by pouring molten metal into a mold
Inlay – Materials such as stones, gems, woods and metals are inserted and cemented into the surface of another material and ground down to create a smooth surface
Iridescence – A rainbow display that is created when light is broken up into different colos like in a soap bubble or oil slick. It is an optical phenomenon.
Irradiation – Exposure of a material to radiation; causes color change in diamonds
Karat – A unit of measure for the fineness of gold; abbreviated “k” or “kt.”
Kimberley Process – Diamond industry program designed to ensure that diamonds crossing international borders are legitimate and do not fund civil conflict or terrorism.
Laser drilling – Using a concentrated beam of laser light to reach a diamond’s dark inclusions and disguise or eliminate them.
Loupe – A small, portable magnifying lens used for examining gemstones and jewelry
Marquise Cut – A stone cut in an oval with pointed ends or a boat-shaped stone
Mineral – A natural, inorganic material with a special chemical composition and crystal structure that repeats itself. Most gems are minerals.
Mohs Scale – Used to rank minerals in order of the hardness on a scale of one to ten.
Millegrain – A decorating style creating a fine bead like effect around the edge of a metal collet
Nacre – The smooth, inside surface of a mollusk shell. It is the same material the mollusk uses to form a pearl.
Octahedron – A crystal shape with eight flat equal sides. Rough diamonds and spinel often form in this shape.
Patina – Discoloration that forms on metals such as silver and bronze but often planned for in the artist’s design, can also be introduced artificially by use of chemicals
Pavillion – The lower part of a cut gemstone below the girdle
Palladium – A white precious metal belonging to the platinum group; it weighs a little more than half as much as platinum and sells for about half the price
Platinum – A grayish white precious metal that is often alloyed with other metals and used to make jewelry.
Pleochroic – Describes a gemstone that desplays two or more colors when you look at it from differetn directions. Alexandrite would be an example of a strong pleochroic gemstone.
Precious Metal - A classification of metals that are considered to be rare and/or have a high economic value. The higher relative values of these metals are driven by various factors including their rarity, uses in industrial processes and use as an investment commodity. Precious metals include: gold, silver, platinum, and palladium.
Precious Gemstone - Only four gemstones in the world are classified as precious gemstones: emeralds, rubies, sapphires and diamonds. The term originates from ancient Greece, Rome, Egypt and Mesopotamia, where the gemstones held ceremonial and historical importance. They were named "cardinal gemstones" for their use by royalty and religious figures.
Plumb Gold - A term used to describe gold jewelry that contains the precise amount of gold in the alloy that the Karat mark indicates. Until 1981 an item marked 14Kt could legally have been 13.5 karat and still considered 14K. Today an item marked 14k must be at least 14 of 24 parts fine gold and is considered plumb gold.
Recutting – Repairing damage or refashioning a polished diamond to improve its clarity, proportions, or color, or to modernize an old-style cut.
Repolishing – Refinishing a polished diamond to correct minor faults in its clarity or finish.
Rhodium - Rhodium is an element, Rh, that is silvery-white and hard. It is one of the rarest and most valuable precious metals. It is resistant to corrosion and does not oxidize. For this reason, white gold is often plated with a thin layer of rhodium to give it a shiny silvery-white color. Rhodium, which is one of rarest elements in the Earth's crust, is found in platinum ores in South Africa and North America. Rhodium is rarely used in its pure form in jewelry because it has a high melting point and poor malleability, and because it is so expensive - about 8 times the price of gold.
Rose Gold - Rose gold, red gold, and pink gold are made from a gold and copper alloy. Since copper has a bold pinkish-orange color, adding this alloy to gold gives the gold a beautiful pinkish gold color.
Scintillation – The flashes of light and the contrasting dark areas you see when the diamond, the light, or the observer moves.
Sterling Silver - Sterling silver is an alloy of silver, which consists of 92.5 percent silver and 7.5 percent copper.
Signet ring – A ring that is engraved or is set with an engraved gem featuring a monogram, crest, or symbol of the wearer.
Simulant (diamond) – Any material that is not diamond or synthetic diamond, but which imitates a diamond’s appearance and is used in its place; such as cubic zarconia, renzite or moissanite.
Single Cut – A simple diamond cut, with a table, eight crown facets, eight pavilion pacets, and sometimes a culet.
Solitaire – A style of ring that only has one center stone; there are no other stones.
Steam Cleaner – A machine that cleans jewelry with high-pressure steam.
Step Cut – A cutting style with long, narrow, four-sided facets in rows parallel to the girdle on both the crown and pavilion.
Synthetic Diamond – Manufactured diamond with essentially the same physical, chemical, and optical properties as natural diamond. This process works for gemstones as well.
Ultrasonic Cleaner – A machine that cleans jewelry with high-frequency saound waves in a liquid solution.
Vermeil – Sterling silver layered with a thin coating of gold
White Gold - White gold is an alloy of yellow gold and at least one white metal, usually nickel or palladium. 18K white gold is 75% gold, and 14K white gold is 58.3% gold, so jewelry made from these metals have a slight yellow color. To enhance the whiteness, almost all white gold is plated with rhodium - a shiny, white metal which is extremely hard. Depending on the amount of wear to a piece of jewelry, over time the rhodium plating may wear off, revealing the original metal color. Jewelry can be re-plated with rhodium to restore the whiteness.