Agate - A form of crypto crystalline quartz or chalcedony, most often banded, onyx, aventurine and carnelian are varieties, mostly fashioned as cabochons and beads

Alexandrite - A rare gemstone that changes color from green in natural light to red in artificial light, not to be confused with the more common Alexandrite-like synthetic sapphire which has a purple to blue color change

Amber - Yellow to brown gemstone less commonin red, green or gray, organic gem from fossilized tree sap, resin or gum, most common cut in cabochon form

Amethyst - Purple gemstone, member of the quartz family, varies in color from light to dark purple, February birthstone, Moh's hardness 7

Aquamarine - A transparent, very light to medium-dark blue to greenish blue variety of beryl, March birthstone

Art Deco - A style of jewelry common in the 1930's featuring angular designs with white metals, sapphires, jade, black onyx and pave and bead set diamonds

Art Nouveau - A style of jewelry common from early 1890's until the 1910's featuring flowing lines of women, butterflies, birds and other figures mainly in yellow gold, many pieces feature enamels and gemstones

Aventurine - A translucent speckled green form of quartz, most often found in beads and cabochons

Baguette - A style of step cut, usually for small rectangular stones mostly used as accent stones, Primarily used for diamonds

Bail - A flat or round wire used primarily as a connecting loop between a pendant and chain

Bakelite - A trademarked name for an opaque plastic or synthetic resin used in the creation of jewelry

Bangle - A narrow non flexible bracelet made from flat or round wire, sometimes many are worn together

Base Metal - Any non-precious metal

Basket Setting - A style of prong setting with open work sides

Bead Setting - A style of setting where the small prongs that hold the stone are made with a beading tool

Bezel - A solid rim of metal that holds a gemstone

Black Onyx - The popular name for black chalcedony, usually artificially colored

Black Opal - An opal with black or dark gray body color

Black Pearl - A pearl with a black or almost black body color

Bloodstone - A dark green opaque chalcedony with spots of red Jasper

Blue-white - An outdated term used to describe a diamond without body color, flagrant misuse has made the term meaningless

Bow - The ring on a pocket watch used to attach it to a watch chain

Box chain - A square link chain

Brilliant cut - The most common cut of diamond consisting of 58 facets: 1 table, 8 bezel facets, 8 star facets, 16 upper girdle facets, 16 lower girdle facets, 8 pavilion facets and 1 culet

Brooch - A piece of jewelry with pin and catch for attaching to a women's clothing

Brush finish - A soft, dull finish on a piece of jewelry

Cabochon - An un-faceted cut of stone with a domed or convex top and often a flat and unfinished back

Cairngorm - Same as Smoky quartz, especially if mined in Scotland

Cameo - A carved gem that is actually a miniature base relief sculpture, cameos are commonly carved from layered stones such as shell and onyx, but is also seen in coral, lava and other stones

Carat - A unit of weight for diamonds and other gemstones, one carat equals 200 milligrams

Carbon Spot - A black appearing inclusion or imperfection in a diamond

Carnelian - An orange-red, brownish red to orange brown form of chalcedony

Casting - Forming a piece of jewelry by pouring molten metal into a mold the shape of the desired object

Chalcedony - A crypto crystalline subspecies of quartz, such as agate, onyx, carnelian, jasper

Channel setting - Stone set between two bars of metal with their edges almost touching

Choker - A style of necklace worn close to the neck, usually 15 or 16 inches long

Chrysoberyl - A gem species of which alexandrite and cat's eye are members, also found in green, brown and yellow

Citrine - A transparent yellow to red orange to reddish brown variety of quartz, birthstone for November

Clarity Grade - The relative position of a diamond's clarity on a flawless to imperfect scale, a flawless diamond having no inclusions or imperfections and an imperfect diamond having inclusion visible to the naked eye.

Clip - A piece of jewelry similar to a brooch but attached with a springed clip rather than a pin

Color grade - The relative position of a diamond's body color on a colorless to yellow scale, GIA's grading scale most common with a grade of D being color less and a grade of Z being very noticeably yellow or brown with all the letters in between representing an increasing level of yellow or brown

Colored Stone - A gemstone of any species other than diamond

Colorless - Devoid of any color as is pure water or a fine diamond

Coral - A gemstone consisting of calcium carbonate secreted by a coral polyp, a small sea animal; coral is usually white, pink, orange or black

Corundum - A mineral species of which sapphire and rubies are members

Costume jewelry - A term ordinarily used to describe jewelry comprised of imitation stones and base metal, however some older costume jewelry contains inexpensive gemstones and gold plated sterling

Cultured Pearl - A pearl produced by artificially inducing the formation of a pearl sac, usually by introducing a bead or piece of shell into a pearl bearing mollusk

Cut - The style or form in which a gemstone has been fashioned

Demantoid - The green transparent variety of Andradite garnet

Diamond - The most cherished and among the most valued gemstones, a mineral composed essentially of carbon in the cubic or isometric crystal system; Most common in colorless to slightly yellow or brown, also less common in orange, green , blue and red; birthstone for April; among the hardest gemstones with a Moh's hardness of 10

Doublet - An assembledstone of two material bound together with a colorless cement

Dwt. - The abbreviation for penny-weight which equals 1/20 of one troy ounce.

Ear nut - A fastener for a pierced friction-back post earring

Edwardian Era - An era of jewelry design between 1901 and 1910, increased use of platinum and elegant design highlight the period

EGL - European Gemological Institute

Emerald - A medium light to dark bluish green variety of Beryl; colored by chromium, a fine emerald is one of the most valued gemstones; the birthstone for May

Emerald cut - A form of step cut, usually rectangular but sometimes square in shape with step faceted sides and corners

Enamel - A vitreous glaze, which is applied to metal in the form of powdered glass usually applied with heat

Engraving - Cutting lines into metal which are either decorative or symbolic

Facet - A plain, polished surface on a gem

Fancy cut - Any style of diamond cutting other than round brilliant cut or single cut

Feather - An inclusion in diamonds that bears resemblance to a feather

Filigree - Ornamental work of fine wire bent into a design and attached to a metal background

Findings - Parts of jewelry produced in quantity used for the repair and manufacture of jewelry such as clasps, catches, spring-rings and ear-nuts

Flaw - Any internal or external imperfection on a fashioned diamond

Fob - An ornament attached by a short chain or ribbon to a watch to remove it from one's pocket

Foil back - A cut piece of faceted glass with a foil back used as an inexpensive gemstone substitute, common in costume jewelry

Full-cut - A brilliant cut diamond or colored stone consisting of 32 facets and a table above the pavilion and 24 facets and a culet below

Garnet - A name that encompasses a number of closely related gem species Several chemically similar elements replace one another freely in the garnet group giving them appreciably different appearances, colors most common are red, purplish red and brownish red but are less common in green, orange and yellow; species and varieties include pyrope, almandite, demantoid, spessartite, rhodolite, grossularite and others, Garnet is the birthstone for January

Gemologist - One who has successfully completed recognized courses of study in gem identification, grading and pricing, as well as diamond grading; e.g., a Graduate Gemologist from the Gemological Institute of America

Gemology - The study of gemstones, their identification, grading and appraisal

GIA - Gemological Institute of America

Girdle - The outer edge or periphery of a fashioned gemstone; the part usually grasped by the setting or mounting

Gold - A yellow colored precious metal and element used in coins and jewelry since prehistoric times; it's hardness of 2-2.5 is to soft for jewelry unless alloyed; gold is the most ductile and malleable of all metals

Gold-filled - A layer of karat gold, joined to a base metal alloy and then rolled or drawn to a desired thickness

Gold plate - A base metal upon which a thin plating of gold has been deposited by electrolysis

Hardness - The resistance a gemstone has to scratches and abrasions

Hematite - A heavy, metallic gray to black gemstone used in beads and often in intaglios

Inclusions - Natural particles or foreign matter which is enclosed with-in a gemstone

Intaglio - To carve or cut a design into a gemstone

Karat - A standard measure of fineness used for gold. 24karat is 100% pure gold, One karat is1/24th, 14karat is 14/24 pure gold and 10/24 is alloy (harder metals).

Locket - A hinged, closable pendant made to enclose a picture or lock of hair

Loupe - A small hand-held magnifier (usually 10 power) used to examine gems and jewelry

Luster - The effect produced by light reflected from the surface of a gemstone or pearl

Matinee - Term used to describe the length of pearls or a necklace( usually 24-26 inches long)

Melee - Small diamonds weighing from under .01 carats to .10 carats

Moh's scale - A scale for hardness used by gemologists. Scale is one to ten, ten being the hardest (diamond).

Mother of pearl -The iridescent interior shell layer from a pearl oyster

Mounting - The frame or setting that holds a gemstone in place

Nacre - Mother-of-Pearl

Nickel silver - A composition that contains no silver, an alloy of nickel, copper and zinc

Obsidian - A natural occurring volcanic glass

Old European cut - An early form of brilliant cut with a round girdle outline but with a high crown, small table and large culet

Old-mine cut - An early form of brilliant cut with a cushion (rounded corner square) girdle outline, old-mine cuts usually have a high crown, small table and large culet

Onyx - One variety of chalcedony, most commonly dyed black in color

Opal - An amorphous mineral, popular in gemstones when it exhibits some play of color

Opaque - Lacking transparency, impervious to light

Opera - Term used to describe the length of pearls or a necklace (usually more than 30 inches long)

Orient - Term used to describe the iridescent play of light in pearls

Paste - An imitation gemstone made of leaded glass, used to describe any imitation gemstone

Pave - A style of gem setting where the stones are set very close together with a minimal amount of metal showing between them

Pavilion - The lower portion of a cut diamond below the girdle

Pearl - A calcareous concretion formed in the body of a mollusk and possessing iridescence (orient)

Pennyweight - A measurement of weight used with precious metal, twenty pennyweight equal one troy ounce, abbreviated dwt.

Peridot - A transparent yellowish- green mineral species, August birthstone

Pink sapphire - A light-red corundum, as distinguished from a medium-red or darker corundum which would be considered a ruby

Platinum - A soft heavy light gray precious metal usually alloyed with iridium to harden (10% iridium platinum)

Point - In weighing diamonds, 1/100 of a carat, a ten pointer would be .10 carats etc.

Polished girdle - A girdle that has been lapped to yield either a lustrous curved facet or a series of flat polished surfaces (faceted)

Prong - The projection of metal that overlaps the girdle of a stones and secures it in the mounting

Pyrope - An intense dark red species of the garnet group

Quartz - The most common and widely distributed mineral among the varieties are amethyst, citrine, agate, onyx, chalcedony, aventurine, bloodstone and many others

Refining - The recovery of precious metals from the mass of other alloys and combinations

Refraction - The bending of light rays as it passes from one optical density to another

Repousse - Raised and modeled designs and motifs 

Rhinestone - Faceted glass with a foil backing used a gem imitation most commonly in costume jewelry

Rhodium - A metal in the platinum group most often used in plating to give a uniform color or to prevent tarnish

Rhodolite - A purplish-red species in the garnet group

Rhodonite - A translucent to opaque, pink to red brown ornamental mineral

Rose cut - An early form of stone cutting which consists of a flat base building to a dome of triangular facets

Rose gold - A gold alloy with a higher copper content giving gold a redder appearance

Rouge - A buffing compound used for polishing made of iron oxide

Ruby - A red variety of corundum, the birthstone for July, intense medium to medium dark purplish red is most desired

Safety catch - A catch that holds the point of a pin-stem in place

Sapphire - Any gem corundum other than red, the birthstone for September, most common in blue, available also in pink, purple, yellow, green and others

Sardonyx - A chalcedony with straight, parallel bands or layers of reddish brown to brown alternating with another color

Scarab - A gemstone fashioned into the shape of a scarab beetle which was worshipped by the ancient Egyptians as a symbol of fertility and resurrection

Screw back case - A threaded watch case where the case back is screwed on to attach to provide greater water resistance

Seed pearls - Small, round, nacreous pearls

Setting - A mounting or the portion of the mounting that holds the gem

Shank - The part of a ring that encircles the finger, exclusive of the setting

Shoulder - The upper portion of a ring shank, near the setting

Signet ring - A ring engraved with initial, monogram, crest or coat of arms

Silver - A soft, white metallic element used in the manufacture of jewelry, silverware, coins and many branches of science, usually alloyed to harden it for use in jewelry and tableware

Single cut - A simple form of gem cutting that has a circular girdle, a table, eight bezel facets and eight pavilion facets, and sometimes a culet. It is mostly used for small diamond melee

Smoky quartz - A smoky grayish-brown, smoky yellow to almost black variety of quartz

Soldering - Joining metals together by melting between them an alloy that flows at a lower temperature than those being joined

Solitaire - A ring or piece of jewelry containing a single gem

Spinel - A mineral species that has transparent red, orange blue, violet and purple varieties

Spodumene - A mineral species that occurs in a transparent form in light tones of red, lilac, violet, green or yellow

Spread stone - A faceted gem that has been cut with a larger table and a thinner crown to retain greater weight

Star ruby - A cabochon cut ruby with six rays

Star sapphire - A cabochon cut sapphire that normally has six rays, rarely twelve

Sterling silver - A metallic alloy consisting of 92.5 % silver and 7.5 % copper, the latter for hardening purposes

Stone gauge - A device used to measure gemstones, such as a Leveridge gauge

Swivel - A clasp most commonly used at the end of a pocket watch chain to attach to the watch

Symmetry - When referring to a faceted diamond, the term means the exactness of placement and shaping of opposed facets and other portions of the stone

Synthetic stones - Man-made stones that exhibit the same structure, composition and chemical properties of a natural stone, most common are synthetic spinel and synthetic sapphire

Table - The large facet the caps the crown of a faceted gemstone

Tarnish - A coating on metals caused usually by the oxidation of the constituents. The black tarnish on solver is silver sulphide.

Tiffany setting - A six-prong setting, generally round in shape and flaring out from the base to the top and having long slender prongs to hold the stone.

Tiger's eye - A yellow or yellowish brown ornamental and gem variety of quartz

Toggle - A long bar shaped piece of metal used with a large receiving ring to form a clasp.

Tone - The attribute of color that determines it's position on a light to dark scale

Topaz - A species of gemstone most common in yellowish brown, pink and light to medium dark blue colors. Most blue topaz is heat treated from a colorless or yellow rough

Tourmaline - A mineral species, gem varieties of which are transparent and of all major hues, although most commonly green or pink, one of the birthstones for October

Translucent - Passing light imperfectly, a translucent material transmits light, but objects cannot be resolved through it

TransparentPassing light clearly, Objects can be seen through it

Treated stone - A gemstone heated, stained or coated to improve or alter it's color

Trillion - A triangular shaped cut usually faceted

Triplet - An assembled stone of three parts held together by a colorless cement

Turquoise - One of the most important opaque gem minerals, the best quality is an intense blue, between light and medium in tone; light blue green varieties less desirable, one of the December birthstones

Tweezers - A tool for quick and efficient handling in watch and jewelry work

Variety - In gemology, a division of a species, based on color, optical phenomena or other distinguishing characteristics of appearance

Vermeil - Silver that has been gilded

Watch - A portable timepiece

Wedding ring - A round band of precious metal given to the bride and groom as part of the wedding ceremony, it may or may not be set with gems.

White gold - Karat gold that is alloyed with nickel and sometimes zinc, copper, tin, etc. It is tougher and harder than yellow gold.

White opal - Opal with a body color of any light color as distinguished from a black opal

Yellow gold - Karat gold alloyed with copper and silver in approximately equal qualities

Zircon - A mineral species that yields exceptionally brilliant, transparent gemstones. Most popular in blue, which is one of the December birthstones, not to be confused with Cubic Zirconia a diamond simulant.