Jewelry Glossary

Describes the purity of sterling silver. .925 indicates that the silver is 92.5% pure silver. The remaining 7.5% is usually copper, and is added to make the silver stronger.

Pure gold is very soft and rarely used to make jewelry. Instead, jewelers use alloys known collectively as karat gold. Karat (K) indicates the number of parts by weight of gold in 24 parts of an alloy. Pure gold is 24K. 10K is 42% gold. The rest may be silver, brass, bronze or other base metals.

A thin layer of karat gold applied over another metal. Also called gold electroplate.

A plating of karat gold over sterling silver jewelry. Also called vermeil.

Pure gold.

The mother of pearl lining of a mollusk shell. Comes in many color combinations, including black, white, brown, green, purple and pink.

Natural half-pearl that forms on the inside of an abalone oyster shell rather than within its tissue. Once it is reworked, it is known as a Mabe pearl.

Natural whole pearl formed in the body of an abalone, a univalve mollusk known for its iridescent pearls.

Muscle responsible for opening and closing a mollusk shell. Sometimes eaten as a delicacy.

A style of ring that is flexible so the size can be altered.

A type of chalcedony quartz with a hard outer shell and a colorful banded center. Prone to scratches and chips, agate must be handled carefully.

The American Gem Society. One of the world’s top diamond grading laboratories.

A high-quality cultured pearl used in premier women’s jewelry. Akoya pearls are grown in the saltwater Akoya oyster and are known for their luster, large size, smoothness and round shape. Farmed in Japan and sometimes China.

A pearl produced by inserting a seed into a Pinctada fucata martensi mollusk.

A mixture of metals used to make jewelry. Soft metals like gold and silver are mixed with other metals to increase strength.

Historical female pearl divers of Japan. There are 2 kinds: kachido worked alone while the funado worked with a partner, usually the husband.

A semi-precious gemstone that ranges in color from delicate lilac to intense violet. The traditional birthstone for February.

A ring including 3 or more diamonds or other gemstones in a prong or channel setting.

A blue variety of beryl. Most aquamarines are treated to improve color, but the color can quickly fade when exposed to sunlight. The traditional birthstone for March.

Calcium carbonate crystals that are stacked in a brick pattern. Aragonite is a component of mother-of-pearl and nacre.

Similar to a square emerald cut but with a higher crown, larger step facets and a smaller table.

An optical phenomenon that occurs in certain gemstones reflecting a star-like shape on the surface of a smooth (cabochon) cut. The star may have 4, 6 or 8 rays.

A ring of coral that encircles a lagoon. Atolls are considered to be the best place to farm the Pinctada margaritifera mollusk.

A popular choice for accent stones in jewelry, baguettes are long and rectangular.

A non-flexible bracelet that is slipped onto the wrist. May also have a hinge.

A ring setting in which gems are held in place and separated by a shared bar.

An irregular or asymmetrical pearl. Freshwater pearls are commonly baroque in shape because they are seeded with tissue rather than a bead.

A term used to describe free-form shaped gems such as pearls, irregular cuts in gemstones, or tumble-polished stones.

A cabochon or faceted gemstone cut in a rectangle with wide sides, resembling a barrel. Popular for men’s jewelry.

A jewelry fastener that resembles two halves of a barrel that screw together.

Name given by Indian pearl dealers to freshly harvested natural pearls from the town of Basra, Iraq.

A pearl grown in freshwater or saltwater that has been started by implanting a bead into a mollusk.

A statement necklace that drapes onto the chest.

A mollusk with a two-part shell attached by a hinge. Some but not all bivalve mollusks produce pearls.

A freshwater pearl grown in a Hyriopsis schlegeli mussel in Lake Biwa, Japan. Sometimes used incorrectly to describe any freshwater pearl.

A pearl-producing mollusk that is either a Pinctada margaritifera or a Pinctada margaritifera cumingi.

A pearl that is naturally dark in color produced by any of the following mollusks: Pinctada margaritifera, Pinctada mazatlanica, or Pteria sterna.

Common whitening treatment applied to most freshwater and cultured Akoya pearls, and sometimes to Tahitian or South Sea pearls.

A flaw on the surface of a pearl, including pits and/or humps. Blemishes may be difficult to detect with the naked eye.

A pearl that is attached to the shell of the mollusk. It may occur naturally or be done intentionally.

A fastening mechanism in which a tab is inserted into a decorative box. Frequently has an additional safety feature to secure the closure. Traditionally used for tennis bracelets.

A set including multiple bracelets, or bracelets paired with other types of jewelry.

A set of rings including the engagement ring and wedding band(s).

A cutting style that improves the optical effect and maximizes brilliance, particularly with diamonds.

A gemstone cut polished to resemble a bullet.

Historical Japanese linear measurement that is still used today to describe the diameter of a bead nucleus. One bu = 3.03 millimeters.

The first cultured pearl produced by the Chinese in the 1200s. A Buddha-shaped nucleus was implanted to spur the growth of the pearl.

A method of removing organic residue from the surface of a pearl to improve its appearance.

A dome-shaped pearl with one flat side. Classified as ‘high’ or ‘low’ based on height of dome.

A ring mounting in which the two sides of the band overlap or crisscross one another but do not meet.

Thread-like tissue secreted by bivalve mollusks to attach themselves to a solid surface.

A chain with oval or round metal links that alternate with matching links.

A polished gemstone without facets.

Many types of mollusks including oysters and conches produce these stone-like growths. All pearls are calcareous concretions, nacreous or otherwise.

A natural crystalline form of calcium carbonate. When combined with conchiolin and aragonite, they make up nacre.

An engraving method used to produce a raised effect on a soft gemstone, often onyx or agate.

Examining a pearl in front of a focused light source to determine whether it contains a bead nucleus.

A weight measure sometimes used for natural pearls. A carat = 4 grain, 200 milligrams and 0.007054 ounces.

A weight measure for gems. For pearls, a carat is 4 grains, 200 mg or 0.007054 oz.

French for ‘square.’ A carre watch case may have blunted or round corners.

A polished gemstone that displays a glowing band of light down the center (chatoyancy), similar to a cat’s eye.

A certified gem has been inspected by a reputable gemological lab and issued a certificate.

A bracelet or necklace made with matching round or oval links.

One of several styles of metal links. The links can match or alternate in size.

Rectangular stones set in a row with metal folded over the edges. Offering protection from falling out, chips and scratches, channel settings are a popular choice for engagement and wedding rings.

A molded or engraved figure that can be made from a variety of materials including glass, plastic, gold, and other metals. Charms are meant to represent passions, special events, or hobbies that are important to the wearer.

A single streak of light usually associated with a cabochon cut similar to a cat’s eye.

A V or upside-down V pattern used in both men’s and women’s jewelry.

A type of metal plating made from a mix of 14K gold and oxidized copper.

A pearl necklace that lies above the collar bone and measures 14-16-inch (35-41 cm) in length.

A type of necklace that fits snugly around the neck.

A pearl with raised, concentric rings on its surface, likely due to the pearl rotating during growth.

A clear yellow type of quartz mixed with iron. Commonly mined in Brazil.

Non-nacreous pearls sometimes found in clams. They are generally low in value.

An industry term describing the number of blemishes and inclusions in a gemstone.

Jewelry fasteners come in a variety of styles, such as spring, barrel, box and hook.

A standard of excellence. A style or pattern that is fashionable for any age or era.

Usually made from gold, silver, or platinum, classic bands may feature diamonds, but tend to be plain in style.

The best way to clean pearls is by wiping them with a soft cloth after each wear. Use a damp cloth and mild dish soap only when needed. Let dry before storing.

A natural or artificial layer applied to pearls to enhance surface quality, luster or other optical effects.

A silvery-white metal that is both strong and malleable. Durable and resistant to scratches, it makes an excellent material for wedding bands.

An oversize ring often set with a combination of gemstones positioned at various heights. Also called a dinner ring, cocktail rings may be fine jewelry or costume, and are worn on the middle or index finger.

A cultured pearl shaped like a coin.

A pearl necklace measuring 10-13-inch (25-33 cm) in length, slightly longer than a choker.

A necklace or strand of pearls that measures 10-13 inches in length.

Pearls come in a rainbow of colors, from classic white to exotic black and every shade in between. Pearls frequently have overtones or a secondary color, including rose, silver, gold, and peacock (a mix of rose, gold, and green).

An industry measurement of color or tinting in a gemstone.

A treatment that alters a gem’s color that may include heat, dye, bleaching, irradiation and oiling.

Rounding the inside (shank) of a ring to create a more comfortable fit.

Two conjoined pearls that give the appearance of a single pearl.

A non-nacreous pearl produced by a conch shell. Rare and valuable, pink is the most desired color.

An organic glue-like substance that bonds aragonite and calcite crystals in a mollusk’s shell and creates the iridescent layer of mother-of-pearl.

A gem shape with a flat, round base that narrows to a point.

A diamond that is sourced, produced and traded without abusing human rights or the environment. May be labeled as Kimberley Process Certification Scheme (KPCS). The term is not all-inclusive and cannot guarantee certain parts of the production process, such as cutting, which may involve(...)

A jewelry style that incorporates more than one metal or color and has more designs than a classic.

Found in the tropics and usually protected, fossilized coral is sometimes used in jewelry. May also refer to a pinkish-orange color.

Pearls cultured in Pteria sterna mollusks in the Sea of Cortez, aka the Gulf of California.

Jewelry made from non-precious materials to copy fashion trends of precious jewels.

The part of the gemstone that lies above the maximum diameter (girdle) and below the flat surface at the top (table).

Transparent form of crystallized quartz used in jewelry. Very durable as jewelry, crystal is used in stemware and figurines.

A synthetic crystal that is an affordable alternative to diamonds or other gemstones. Cubic zirconia is not a mineral.

Freshwater pearls are grown on farms in ponds, rivers, or lakes. The process is still usually carried out by hand. The largest producers of freshwater pearls are the US and China.

A pearl produced by inserting a bead or tissue graft into a mussel or mollusk. The main difference between cultured pearls and natural pearls is cost, cultured being more affordable.

A pearl created by inserting a bead or tissue graft into a mollusk.

A style in which matching oval links are twisted and flattened. Popular with both men and women for its strength, flexibility and ease of repair.

A square cut with rounded corners, similar to a cushion.

The quality produced by cutting a stone in a specific manner to enhance a gem’s natural beauty. There are numerous types of cuts, including brilliant, step, and mixed.

Rhinestones that have been faceted to create an 8-pointed star design.

The French word for rhinestone.

A transparent carbon crystal, diamonds are the hardest known material. The word ‘diamond’ comes from the Greek ‘adamas’ meaning ‘invincibile.’ Highly prized for their ability to split light into rainbow colors.

One way nacre layers split light into rainbow colors, sometimes displayed as an overtone.

The separation of white light into rainbow colors. Gemstones which have been well cut maximize this effect.

A rounded, convex shape with a flat back that is thickest in the middle and tapers toward the edges.

An earring style which hangs down from the earlobe.

Two different color and metal types, such as yellow gold and sterling silver.

Cultivated pearls that are made colorful by immersion in dye.

Artificial coloring of pearls to enhance hue, or to create pearls in colors not found in nature. Pearls are usually dyed after drilling to improve color absorption.

A cut with 8 upper and 8 lower cuts plus a table, resulting in 17 facets. Used when a diamond is too small for full cuts.

One of the most valuable gems, emeralds can range from medium to dark green. Inclusions are common and considered part of the stone’s character. The traditional birthstone for May.

Shaped like a rectangle with trimmed corners. The shape was originally developed for cutting emeralds.

A glassy, usually opaque, decorative substance that is baked onto metal, ceramic or glass.

A ring that indicates the person wearing it is engaged to be married.

The art of cutting decorative lines into metal or other materials.

A type of anniversary ring in which a continuous row of gemstones, often diamonds, encircle the entire band.

Guided by principles that promote human and environmental well-being, and avoiding those that do harm.

Cultured freshwater pearls that exhibit unusual colors, such as blue, orange, green or gold.

A hand-held magnifying glass used by jewelers to examine gems.

A cut in a gemstone that catches and reflects light.

A general term that does not have any single standard or protocol to be measured against. Fair trade may mean that the goods help producers in developing nations improve human health, socioeconomic and/or environmental conditions.

A label given to gold and silver that is sourced only from small-scale and artisan mining organizations. The mines must meet the requirements of the Alliance for Responsible Mining (ARM).

A gemstone cut into a popular shape, such as a heart or flower.

Jewelry that contains decorative elements including gemstones and crystals.

Any imitation pearl manufactured by coating a glass or plastic sphere with a pearlescent coating that is sometimes pearl powder.

A cultured pearl grown in the fancy shape of a bird feather.

Thin metal wire that has been twisted into delicate patterns.

A jewelry component such as a clasp, setting head or bail.

A general term to indicate an imperfection which negatively impacts the physical or optical nature of a gemstone. Flaws include feathers, stains, clouds, internal crystals, and mistakes in cutting or polishing.

A reaction of trace minerals within a diamond that causes it to glow when exposed to UV light.

A common diagnostic tool used to determine whether a pearl has been dyed.

An industry term that includes the 4 values used to rate diamond quality: cut, color, clarity and carat.

Black glass which is an imitation of jet.

Diamonds set snugly but with the sides visible to allow more light to enter, adding extra sparkle and brilliance.

Pearls that have been farmed in lakes, ponds or rivers. Freshwater pearls are not perfectly round and offer a wider range of colors. They tend to be less expensive than saltwater pearls.

A pearl produced by inserting a bead or tissue graft into a mussel that lives in non-saline water.

A pearl grown in a mussel that lives in non-saline water. Freshwater pearls tend to have a more freeform shape than saltwater pearls.

Pearls said to come from the tusk sockets of elephants.

A gem in colors that can range from pale rose to a deep red-black. Garnets can be found in larger cut sizes, generally have good clarity, and are relatively hard, making them a good choice for jewelry. The traditional birthstone for January.

A type of univalve mollusk with a head and eyes, including land and sea snails.

A precious or semi-precious mineral used as jewelry when cut and polished.

A genuine gemstone comes from nature and is not man-made.

The Gemological Institute of America is a not-for-profit, independent authority on gemology.

A decorative technique in which gold is applied to a solid surface, such as metal, porcelain or stone.

The widest section of a cut gem where the pavilion and crown meet.

Made from sand, glass can be dyed any color and is often used in costume jewelry.

A precious metal and a top choice for jewelry. Because gold is very soft, it is usually alloyed (mixed) with other metals such as copper or silver to make it stronger. The amount of gold is represented by karats (K). Pure gold is 24K.

A type of metal made by bonding a layer of gold with a second, less expensive metal using heat and pressure. The FTC requires the weight of gold to be at least 1/20 of the total weight, and must achieve a minimum classification of 10K. Gold-filled jewelry has a much thicker layer than gold-plated.

The Pinctada maxima mollusk that produces gold South Sea pearls. The edges of the shell’s interior are golden in color.

A thin layer of metal deposited onto a less expensive metal using electrolysis or chemicals.

Gold tone jewelry has been electroplated. It provides a rich look at a fraction of the cost of real gold.

The reproductive organ of pearl-producing mollusks where the bead or tissue graft is implanted to produce cultured pearls.

A strand of pearls in which the pearls increase in size a minimum of 3 mm from end to middle, with the largest at the center.

The insertion of tissue into a mollusk to produce a cultured pearl.

A unit of weight used with natural pearls. One grain = 0.25 carat.

French Polynesian term to describe the grafting process.

A type of ring worn with and encompassed by an engagement ring. It may be the wedding band or worn in addition to the band, creating a coordinated wedding ring set.

To protect a gem from scratches and chips, the stone is set flush with or slightly below a protective metal band on 2 sides.

A pearl that has been drilled to 2/3 or 3/4 of its diameter in order to be set in a piece of jewelry.

Frequently used as an accent stone around a larger, central stone, a half moon gem has a straight edge on one side and a curved arc on the other.

The type of gastropod more commonly known as abalone. The shell is extremely strong with tiny tiles of calcium carbonate stacked like bricks.

A style of engagement ring featuring smaller diamonds encircling a central stone.

A minimum pearl quality standard set by The Pearl Science Lab in Japan.

The Japanese term for a cultured blister pearl, which is a pearl attached to the inner surface of a mollusk shell.

A gem’s ability to resist scratches. The Mohs Scale rates hardness from 1 to 10, with 10 being the hardest.

An iron oxide that is opaque and usually a deep gray-black with a metallic luster. Often cut into beads.

The first impression of gem’s color.

The pearl mussel native to Japan used to produce cultured freshwater pearls in Lake Biwa. Also cultivated in China.

Any artificial pearl created by coating a glass or plastic sphere with a pearlescent coating that is sometimes pearl powder.

A foreign material, usually small, in a mineral.

Interference of light by nacre creates a variety of colors on a pearl’s surface.

A technique invented by Van Cleef & Arpels to set stones from the back so that no metal mounting shows, creating the impression of a single large stone.

An advanced surface finishing process that involves adding a titanium nitride layer in vapor form to a base metal. Ion plating creates a harder, more durable surface and an improved brightness and sheen than other plating methods. Also called IP Plating.

Insurance Replacement Estimate. An estimate of jewelry value used by insurance companies.

Color play on the surface of a pearl caused by light being split into its component colors.

A rainbow-like effect or feature of jewelry that shows different colors when viewed from different angles.

A process in which a cultured pearl is exposed to gamma rays to darken the nacre.

An organic gem formed in the tusks or teeth of certain mammals including elephants, narwhals and wild boars. Ivory is very soft and most often used for carving and engraving. Due to the decimation of certain species caused by the collection of ivory, importing ivory into the US is illegal.

A type of earring that loops through the earlobe and resembles the letter J.

Both nephrite and jadeite can be made into jade. Jadeite is considered more valuable due to the intensity of its color, translucency and rarity. Jade ranges in color from emerald to mottled green, and also black, white, pink and yellow.

Metal treated with a black lacquer.

A type of coal formed by heat, pressure and chemical reactions on ancient driftwood that can be carved, polished, faceted and engraved. Commonly used in the 19th century as mourning jewelry.

A type of gift set featuring matching earrings and a necklace.

A jewelry style containing at least 4 stones of different sizes, arranged in order from smallest to largest. The design is meant to signify the growth of love over time, and also important turning points or steps along one’s life path.

Historical Japanese unit used to weigh pearls. One kan = 1,000 momme, 3.75 kilograms or 8.26 pounds.

A measurement of the amount of pure gold in an alloy. The amount of gold can be calculated by diving the karat number by 24.

A small, round pearl. Also referred to as seed pearls.

A small natural or cultured pearl. The term comes from the Japanese word for ‘poppyseed.’

A gem carved into the shape of a kite. Five matching kites are sometimes used to create a star pattern. Also called a diamond cut.

Before culturing black-lip pearl oysters in French Polynesia became popular, most black pearls came from La Paz Pearl Oysters in Panama or Baja California.

A natural drop-shaped pearl found in 1513 in the Gulf of Panama by the Spanish explorer Balboa and given to King Philip II of Spain.

A manmade diamond. Lab grown diamonds have the same physical, chemical and optical characteristics as natural diamonds and are nearly impossible to differentiate from mined diamonds.

A deep blue gemstone that sometimes has white or brass-colored inclusions.

A curved wire used as an earring mount that resembles a fish hook. Often used with dangle-style earrings.

Carolus Linnaeus was the first person to culture whole pearls. He also created the classification system of plants and animals used today.

A fastener held closed by a spring, named for its pinching mechanism. Frequently used on necklaces and bracelets, lobster clasps are easier to open than some other types of fasteners.

A necklace that opens to reveal a small personal memento, such as a photograph or engraving. Usually heart-shaped or oval.

Part of the pearl farming process. Lines are stretched between buoys and anchored to the bottom at both ends. Vertical lines (chaplets) with baskets of mollusks are suspended from the longlines.

Markers or numbers that glow in the dark.

The quality and quantity of light reflected from the surface of a pearl. High-quality pearls appear to be illuminated from within. Thicker nacre usually results in better luster.

The quantity and quality of light reflected from the surface of a pearl.

A blister pearl grown in Pteria penguin mollusk, then hollowed out and filled with a substance and backing.

A pearl shape in which one side is rounded while the other is flat. Naturally occurring mabe pearls are extremely rare.

A device used by jewelers to measure ring size.

A deep-cleaning process used in Japan before bleaching Akoya cultured pearls. Also used to describe several processes used to enhance the luster of most Chinese Freshwater and some South Sea pearls.

A gem with attractive swirling green hues ranging from forest to light green. Named for its resemblance to the leaves of the mallow plant.

The organ that lines the shell of bivalve mollusks and secretes nacre.

With a capital ‘M’, a genus of freshwater mussels. With a lowercase ‘m’ (Pinctada margaritifera), a species of black-lip mollusk.

A modified brilliant-cut resembling a football. The marquise cut highlights the perceived size of the gemstone.

A group of pearls used for comparison to assess the quality of cultured pearls submitted for grading.

Refers to a strand in which the pearls are uniform, either in graduated size or all the same size.

An engagement ring, and wedding bands for the bride and groom in a matching style.

A pearl necklace measuring 20-24 inches (50-60 cm) in length. Matinees have a slimming effect. It is the classic length for an Akoya pearl necklace.

A necklace or strand of pearls that measure between 20-24 inches in length.

A natural pearl that is extremely beautiful.

Marine gastropod that produces the non-nacreous Melo pearl. Rare and very valuable.

First person to commercially produce round cultured pearls using the Mise-Nishikawa method.

Rows of tiny raised metal beads along the edge of a piece of jewelry, usually in a ring.

A large and diverse category of invertebrates, some of which produce pearls.

A Japanese unit of weight for cultured pearls. One momme = 3.75 grams.

The iridescent lining of the inner shell of some mollusks. When it coats a bead to form a cultured pearl, it is called nacre.

A custom ring set with birthstones representing each of the wearer’s children or grandchildren. Traditionally set in a row, mother’s rings are now also available in cluster settings.

A term for an engagement ring setting. The mounting includes the head and shoulders of the ring. May also refer to the placement of the central stone and the surrounding details.

A type of ring for women in which multiple gemstones are clustered together, creating the illusion of a single, large stone.

The lovely iridescent substance that forms inside a mollusk and is commonly called mother-of-pearl. Made of aragonite, calcite and conchiolin.

A gemstone created by nature that has not been treated or enhanced in any way.

A pearl that has formed in a mollusk without human intervention. Very rare and thus valuable.

Extremely rare pearl from the Nautilus pompilius. Imitation Osmenda pearls are sometimes incorrectly named nautilus pearls.

Credited, possibly by mistake, with discovering the bead-and-tissue method of pearl culture.

A natural pearl lacking a nacreous surface. Non-nacreous pearls appear to be denser and more like porcelain.

The process of implanting a bead in a mollusk to become the core of a cultured pearl.

The bead implanted into a mollusk to form the core of a cultured pearl. The most common nucleus is a mother-of-pearl bead.

A bead implanted in a mollusk to become the core of a cultured pearl.

A gemstone shape inspired by the rugged look of a nugget of gold.

A glassy volcanic stone. Normally black, obsidian can also be brown, gold or even white. Used in ancient times to make weapons and mirrors.

A shape unique to Swarovski with multiple facets to catch light.

Gem shape with 8 equal sides.

Earring back shaped like the Greek letter Omega. Usually used with hoop earrings.

A type of quartz or chalcedony. Opaque black with crisp lines that give each piece a unique appearance, onyx has a striking appearance that makes it very popular for jewelry. Usually smooth-cut into cabochon.

A beautiful iridescent stone with shifting colors due to tiny internal structures that reflect the light and create a shimmering effect called ‘fire.’

A pearl necklace measuring 28-35 inches (70-90 cm) in length. Dramatic and meant for glamorous evening events, opera length necklaces can be worn as a long single strand or doubled.

A necklace or strand of pearls that measures 28-30 inches in length.

Used to alter the color of cultured and natural pearls. Organic dyes may produce a more original effect, but can be difficult to replicate.

Sometimes used to change the color of pearls and other gems.

An optical phenomenon producing iridescence in some pearls. Diffraction, refraction, reflection and thin-film interference may all cause orient.

Historical term for natural pearls from the Red Sea and Persian Gulf.

An elliptical shape, it can be considered midway between round and marquise. An oval cut creates the illusion of a larger stone.

Gold plate applied over a silver base.

Secondary color on the surface of a pearl created by the nacre splitting light into component colors.

A reaction with the environment leading to tarnish on a metal. Sometimes done intentionally to achieve a certain effect.

A process of controlled oxidation to cause silver to tarnish.

Common name for some bivalve mollusks. True oysters do not create nacreous pearls.

Chalk-like natural pearls produced by edible oysters that have a low commercial value.

A lustrous silver-white metal that is 15 times rarer than platinum. Palladium plate is palladium that has been applied over another base metal, such as silver.

A matching set of jewels meant to be worn together.

A term used for glass that has been cut and faceted to look like a precious gem.

Small stones set close together so that very little metal shows between them.

The section of a gemstone below the widest section (girdle) and above the bottom facet (culet).

Hue commonly associated with black pearls. Colors range from dark green-gray to blue-gray with rose and purple overtones.

A hybrid between an oval cut and a marquise cut, a pear cut is tapered at one end.

A smooth, lustrous mass formed in certain bivalve mollusks and valued as a gem.

Grown to contain an intruder or implanted bead, it deposits nacre to form a pearl.

Removing the outer nacre layers of a cultured pearl to improve quality.

A pair of natural pearls with the same name. The first is round and weighs 111.5 grains; the second is drop-shaped and weighs 133.2 grains.

A decorative ornament that hangs from a necklace, earring, or pin.

Sometimes called chrysolite or olivine, its color is its most important quality. Hues can range from yellow-green to brilliant chartreuse. The traditional birthstone for August.

Customization of jewelry through a variety of methods including engraving, gem selection, and other specifications.

A silver-gray alloy of tin and copper.

Mollusk which produces Akoya pearls. Akoyas were the first pearls to be cultured, which took place in Japan in the 1920s.

A general term that encompasses all Akoya mollusks regardless of where they grow.

Black-lip mollusk that produces Tahitian and Cook Island cultured pearls.

Synonym for Pinctada fucata martensi, a mollusk that produces Akoya pearls.

The silver- or gold-lip pearl mollusk used to produce South Sea cultured pearls.

Mollusk native to the Gulf of California and the Pacific Ocean in Mexico and Central America.

Pearl-producing mollusk with a wide distribution, living in both hemispheres and most oceans and seas around the world.

The process of coating a surface of a less valuable metal with a thin layer of a precious metal to improve durability and resist corrosion.

The heaviest of the precious metals. A very strong, silver-white metal, platinum resists scratching and fading. Popular for engagement rings and wedding bands, platinum is also hypoallergenic and never needs replating.

A unit of weight in the gem industry. One point equals 1/100 of a carat.

Any material including gemstones and metals recovered from used consumer goods and reused for new products.

A pearl shape that is oblong and irregular, like a potato.

Material recovered from the manufacturing process, or uncirculated goods that are reclaimed to make new products.

Gems which are considered to be rare and have a remarkable color and brilliance. Diamonds, sapphires, emeralds and rubies are all considered precious.

A pearl necklace measuring 17-19 inches (43-48 cm) in length. A modern classic, princess length necklaces are extremely versatile and elegant as they go effortlessly from day to evening.

A square, stepped shape. The second most popular shape for a gemstone, behind the round brilliant cut.

A ring that pledges a commitment, also called a pre-engagement ring. Generally less expensive than an engagement ring.

A narrow metal strip folded over the girdle of a gemstone to attach it to its setting. A common setting for engagement rings.

The relationship between the facet angles and other sections and how they impact brilliance and the gem’s profile.

A voluntary quality-control system introduced in 1999. The tag indicates that a strand of cultured pearls meets minimum quality standards.

One of the most common minerals on Earth. Quartz offers a wide variety of stones used for jewelry. Types include amethyst, bloodstone, agate, jasper, citrine, smoky quartz and rose quartz.

A necklace or pearl strand measuring 31.5 inches (80 cm) in length.

A square or octagon gem that has its corners cut in a straight line rather than rounding them off. A combination of a princess cut and a cushion cut.

Pearl from the Pinctada mazatlanica exhibiting colors like those from the black-lip mollusk, Pinctada margaritifera.

Cut in the form of a rectangle with trimmed corners.

Gemstones and/or metals that have been purchased or used by consumers (post-consumer), or are a byproduct of manufacturing (pre-consumer), or a finished good that never entered circulation (pre-consumer) and is reused in the production of new products.

Overproduction of algae, also called algal bloom, that can weaken or kill mollusks by consuming all the oxygen in the water and/or poisoning them when the algae die. Red tide is not a true tide, nor is it always red.

A measurement of how light is bent as it passes through a gemstone. Refractive measurements are unique to each individual mineral and can be used as an identifying characteristic.

The measurement of light as it bends from one substance to another, such as from air into nacre. The refractive index of natural and cultured pearls is 1.51-1.66.

A colorless glass or crystal stone that is cut and faceted to look like a diamond.

A small oval or egg-shaped pearl with a crinkled surface.

A small, oblong pearl that resembles a grain of rice. Rice pearls are often strung together in multiple strands.

A disc-shaped metal ornament placed between beads and often set with rhinestones.

A pearl strand measuring more than 45 inches (115 cm) in length. A luxurious length that offers multiple options including looping and knotting.

A pink-tinted gold obtained by alloying gold with copper and silver.

The most popular cut for gemstones. Usually faceted to catch and reflect light.

A perfectly round pearl, or one whose diameter does not vary by more than 2%.

The red variety of corundum; all others are sapphires. One of the most highly-prized colored gemstones. Colors range from pink to orange to purple to brownish-red; mid- to deep red is often the most valuable. Corundum is very hard, making it an excellent choice for jewelry. The traditional(...)

An extra chain used as a security measure in the event the clasp opens.

A second fastener used as security measure in the event the primary clasp fails.

Pearls that have been farmed in saltwater. They tend to be rounder and more regular in shape than freshwater pearls. Types include Akoya, Tahitian, and South Sea.

A natural or cultured pearl produced by a mollusk living in saltwater. Usually round, saltwater pearls often have a thinner nacre coating than freshwater pearls, which are almost entirely nacre.

The only stone harder than a sapphire is a diamond. Renown as a brilliant, rich blue, sapphires actually come in a variety of colors, including white, yellow, green and pink. The traditional birthstone for September.

Metal finish used to blunt the shine and produce a softer luster.

A pearl strand measuring more than 36 inches (90 cm) in length. A sautoir is also sometimes called a rope.

A non-nacreous pearl produced by a mollusk of the Pectinidae family. Scallops can swim and are the only migratory bivalve.

The flashes and sparkles produced when a translucent gem is struck by light.

An earring held in place by an adjustable screw.

A tiny natural pearl weighing less than 1/4 grain and usually measuring less than 2 mm in diameter.

A natural pearl measuring smaller than 2mm in diameter.

Any gemstone that is not a diamond, emerald, sapphire or ruby. It is misleading to consider semi-precious gems to be less valuable, as they can be rarer, more valuable, and of finer quality than precious gems.

Two or more rings of a similar style or theme that are sold together. Rings sets can be stackable or multiple sizes.

Describes the overall ring design including engravings, accents, side stones or other work on the band. Usually used in reference to engagement rings.

The part of the ring that goes around the finger. The setting is attached to the shank.

Pearls come in a wide variety of shapes, including round, ringed, button, drop and baroque.

Describes the basic form of a gem, such as round, square, pear, etc.

Shells come from sea creatures such as mollusks. Shell jewelry can be delicate and needs careful handling.

Imitation pearl made from a mollusk shell, aka mother-of-pearl. The nacre is pulverized and mixed with other materials to form a pearl.

Japanese word for pearl. The method for culturing pearls was developed in Japan in the 1920s.

Sterling silver is 92.5% silver alloyed with 7.5% other metals.

A layer of silver applied to a base metal. Plating will wear away over time.

An imitation pearl often made of shell, glass, ceramic or plastic.

Describes the diameter of a pearl. Anything below 7 millimeters is called ‘dainty’; 7 to 8 millimeters is a classic ‘wear anywhere’ size; while those greater than 8 millimeters are considered to be ‘luxury.’

A piece of jewelry made entirely of one metal, or the least amount of other metals needed to ensure sufficient durability.

An elegant, classic style designed to let a single gemstone shine.

Pearls from the South Sea are usually larger than average, and are a brilliant, shiny white. Cultivation is difficult, making this type of pearl rare and more expensive.

A premier saltwater pearl that is famous for its large size, rich luster and delicate hues ranging from white to cream, silver, pink and gold. South Sea Cultured pearls are grown by the Pinctada maxima oyster in the area stretching from China to Australia.

Pearl produced by the Pinctada maxima mollusk. Usually larger than the average pearl, South Sea pearls tend to be exceptionally smooth and round, making them highly desirable.

Saltwater mollusk larva that is old enough to attach itself to a fixed surface but does not yet have a shell.

Known as ‘the great imposter’ of ruby. Spinels come in a wide array of colors, including any combination of white, blue, pink, purple and orange.

A square, stepped shape. The second most popular cut behind round brilliant.

Durable, lightweight and resistant to corrosion, stainless steel is an alloy of iron-carbon mixed with chromium and nickel. More affordable than many other metals.

A precious metal that is less expensive and more widely available than gold.

Also called the queen conch, a large mollusk that lives in the Caribbean. Pearls correspond to the color of the inner surface of the shell and are very rare.

Pierced style of earring with a single gem or precious metal that is often round.

One of the factors considered when determining the quality of a pearl. A strand of pearls without blemishes is very rare.

One of the quality factors considered when grading a pearl.

Actions including sourcing, production, sale and distribution that protect the environment and the well-being of humans.

A type of leaded glass that has been cut to catch the light. Used in jewelry and figurines.

A pearl that is exactly the same shape on both sides of the central axis.

Manmade gem that has been created in a lab. Synthetic gems have the same chemical, physical and optical qualities as natural gems.

The large, flat facet on the top of a gem.

A simple cut with a very large, flat area. Often used for men’s rings or seals.

A type of pearl known for its large size and dark colors. Usually black, Tahitian Cultured pearls can also be gray or green. Despite its name, Tahiti does not have any pearl farms. The pearls are cultivated around French Polynesia.

Produced in French Polynesia by the black-lip (Pinctada margaritifera) mollusk.

A long, thin gem that is smaller at one end so it fits snugly with other baguettes.

Term used by the original inhabitants of French Polynesia for the local black-lipped pearl oyster.

A hybrid between an oval cut and a marquise cut, with a tapered point at one end.

A thin, flexible bracelet with diamonds or other gemstones stretching the entire length.

Opposite ends of the setting hold the gemstone in place by tension, creating the effect of a floating gem.

A type of jewelry that represents the past, present and future of a relationship.

Diluted dye that produces a slight change in a pearl’s color, often pink.

As strong as steel but about half the weight, silvery-white platinum resists tarnishing, making it an ideal choice for jewelry worn daily.

A fastener style with a bar on one end that is inserted into a ring on the opposite end.

A synonym for color, meaning the main color of a pearl. Overtones are secondary colors seen in a pearl.

A hard gemstone found in a range of colors including pink, red, blue, yellow, orange, clear, and brown.

Carats indicate the weight of a gemstone. The standard unit is 200 milligrams and is made in 1/8 increments. In jewelry with more than one gemstone, the carats may be described with a total combined carat weight of all the stones in the piece.

The sum of the weight of all gems in a piece of jewelry.

A richly-hued mineral available in an array of colors. Single color tourmaline is rare. Can be dichroic, meaning the stone appears to change color when angled into different lighting. Pink or red tourmaline is an alternative birthstone for October.

Any action other than polishing that alters a pearl’s appearance, including bleaching, heating, waxing, irradiation, drilling, working and cutting.

Jewelry made with 3 different colored metals, such as gold, rose gold and silver.

A matched set including the engagement ring and wedding bands for the bride and groom.

A way to improve durability or enhancing visual impact of a gem by sandwiching it between glass or less valuable stones. A thin layer of glass is applied to the gemstone and a more durable stone is adhered to the bottom, providing necessary heft underneath.

Valued for thousands of years for its sky-blue color. Blue shades are due to the presence of copper while green shades come from iron or chromium. A cousin to lapis lazuli.

A piece of jewelry with two different metal shades.

A species of freshwater mussel, many of which produce small, irregular pearls with good luster.

A combination of sterling silver, gold and other precious metals. To be considered vermeil, the gold must be at least 10K and 2.5 micrometers in thickness. Gold vermeil is considered the best of all gold-plated jewelry.

A type of treatment used to enhance a pearl’s luster. Sometimes called ‘maeshori.’

Ring worn to indicate that the wearer is married. A symbol of commitment.

Usually created by alloying yellow gold, copper, nickel and zinc, and then plating with rhodium.

The removal of nacre layers from a pearl to improve its appearance. Luster treatments such as working can be difficult to detect with the naked eye.

A type of ring worn with an engagement ring. It may be the wedding band or another band, creating a coordinated wedding ring set.

Used to determine whether a pearl is natural, cultured, or imitation.

An alloy of gold, copper and silver.

Brilliant gem with an intense ‘fire.’ A classic gemstone, zircons are available in a range of colors.

The metal zircon is treated with a heating process that makes the outer layer of the metal extremely durable. Gray and white before treatment, zirconium turns black when heat is applied.