Adularescence
An optical phenomenon that is produced in gemstones, such as moonstone; a milky, bluish-white glow caused by scattering of light.
Agate
A variety of the quartz chalcedony, mostly known for its many different bands of color. It can also display other colorful patterns that look like branches or landscapes.
Alloy
A mixture of two or more metals used in jewelry manufacturing.
Alluvial
A deposit on the earth’s surface formed by the action of running water like a river or stream. It contains valuable minerals such as gold, diamonds, or colored gemstones.
Amulet
An object or charm worn on the body, believed by some to prevent disease or misfortune.
Anklet
A piece of jewelry that is worn around the ankle.
Appraiser
A person who evaluates an item to find out its worth.
Asterism
An optical phenomenon in some gemstones such as sapphire. Crossing bands of reflected light in the gemstone create a six-rayed star-like appearance. It occurs in the dome of a cabochon.
Atom
The basic structural unit of all matter; nature’s building block.
Auction House
A company that places items up for bid at a public sale. Items are sold to the person who bids, or offers, the most money.
Aventurescence
An optical phenomenon that displays a glittery effect caused by light reflecting from small, flat inclusions within a gemstone.
Badge
A distinctive emblem showing membership or office. Early badges were sometimes sewn onto garments, but later they were pinned on hats or clothing.
Baroque
A pearl that has an irregular shape.
Basalt
A fine-grained dark igneous rock that forms when magma cools and solidifies at or near the earth’s surface
Belle ´Epoque
A period in European history that began in the late 19th century and lasted until World War I began in 1914. It was a time of peace and optimism, technological and scientific discoveries, and artistic advances. Belle ‘Epoque means “Beautiful Era” in French.
Bench Jeweler
A person who makes or repairs jewelry.
Beryl
Beryl is a gem species that includes emerald, aquamarine, and morganite, as well as other gem varieties.
Binocular Microscope
A tabletop magnifier with two eye pieces.
Birthstone
A gem, or gems, representing the month in which a person is born.
Bracelet
A piece of jewelry worn on the wrist.
Bronze
A reddish-brown metal that is predominantly composed of copper alloyed with tin.
Cabochon
A polished gemstone shaped like a dome.
Calcite
A white or colorless mineral which is sometimes present where other gems are found.
Cameo
A gem carving style in which a design, often a woman’s profile, projects slightly froma flat or carved surface. Cameos are typically carved from gemstones and seashells.
Carat
A unit of measure for gemstones; equal to 0.2 grams or 200 milligrams; abbreviated as “ct.”
Carnelian
A yellow-orange to orangy red, brownish red or brownish orange variety of chalcedony that can be semi-transparent to translucent.
Chalcedony
A gem and form of quartz that can come in many colors and color patterns. Agate, carnelian, chrysoprase, and jasper are varieties of chalcedony.
Chandelier
An earring style that features multiple elements hanging from a central point.
Charm
A small ornament that can be attached to a piece of jewelry such as a bracelet. These ornaments usually mean something special to the wearer and are often keepsakes from important events.
Chatoyancy
A display of a band of light, like a cat’s eye. It is an optical phenomenon caused by the reflection of light from many parallel, needle-like inclusions inside a cabochon.
Chemical Composition
The unique combination of atoms that make up a material. In a mineral, it is like a recipe that makes the crystal grow a certain way.
Choker
A short, tight necklace that hugs the throat.
Chromium
In ruby, the metallic element that causes red color. It also causes the emerald’s green color.
Chrysoberyl
A mineral whose most expensive variety is alexandrite, which can change color under different lights.
Claddagh
A type of ring with two hands (one left and one right) that clasp a heart topped with a small crown. The Irish Claddagh ring may be given as a token of friendship or love.
Clarity
Describes the visibility of inclusions in a gemstone; the less you can see, the more clear the gemstone. Also, there are gemstones with inclusions that cannot be seen with the unaided eye.
Coat-of-Arms
A symbolic shield or emblem identifying a relationship to a person, family or country.
Copper
A reddish metal that is used, either alone or mixed with other metals, to make jewelry and decorative items.
Corundum
A mineral that includes the varieties sapphire and ruby.
Crown
A headdress worn by a monarch.
Crystal
A solid material with flat surfaces and angles caused by its small sets of repeating atoms, like building blocks that form its geometric shape.
Crystal Structure
A set of atoms arranged in a three-dimensional, symmetrical pattern. A crystal is made up of small sets of atoms that are repeated over and over again, like building blocks.
Cuff
A C-shaped bracelet worn on the wrist or arm.
Cuff Link
A decorative piece of jewelry used to keep buttonless shirt cuffs closed.
Cultured Pearl
A pearl that is grown in a mollusk with the help of humans.
Curator
A person in charge of the collection, authenticity, display, and cataloging of museum pieces. A gemologist can be a curator in the gems and minerals area of a museum, or for a private collection.
Darkfield Illumination
The lighting of a gemstone from the side. It is lit against a black background that does not reflect light.
Deposit
A concentration of valuable minerals. They are found in a host rock or a place futher away from their source due to erosion.
Diadem
An ornamental headband worn on the forehead. Historically, it was a symbol of power.
Durability
A combination of three factors: hardness, toughness, and stability. It is one of the things that make a gem desirable.
Dzi Bead
A type of agate bead believed by Tibetans, Nepalese and other cultures to be of divine or supernatural origin. Dzi beads are believed to offer protection against evil and disease.
Earring
An ornament worn on the ear.
Enameling
A jewelry manufacturing technique where powdered glass is fused onto metal and used to decorate the surface of jewelry, watch dials, or objects.
Encrusted
An item that is decorated lavishly or covered with gems.
Engraved
An object, item of jewelry, or a gemstone with a design cut into its surface.
Erosion
The movement of rock materials by natural forces, such as water, wind, and ice.
Faceted
A gemstone or gem material that is polished, with many flat surfaces called facets.
Fede
A type of ring with two clasped right hands engraved or molded in metal. Historically, fede rings were given as engagement rings or tokens of affection.
Feldspar
A mineral group that makes up around 60% of the earth’s crust. Moonstone is the most well-known feldspar gemstone.
Festoon
A decorative chain of flowers, foilage, fruit, or ribbons, usually hung in a curve.
Field Gemologist
A gemologist who travels to mining areas to study their gems and the latest gem mining information. They also collect gemstone samples.
Filigree
A lacy or delicate style of jewelry design using thin, intricately interlaced wires made of gold, silver, or other metal.
Fluorescence
A light produced by some materials when they are exposed to high-energy sources such as UV light, X-rays, or lasers.
Funerary
An object or piece of jewelry created to be buried with the dead.
Gem
A mineral that is beautiful, rare, and durable. It also refers to a stone that has been cut, polished, and used in jewelry.
Gemologist
A person who studies gemology.
Gemology
The study of gems.
Geologist
A person who studies geology.
Geology
The study of the earth.
Gilded
An object made of metal, wood, or other material that is covered with a thin layer of 24K gold leaf or gold alloy.
Gimmel Ring
A type of ring with two, sometimes three, parts that fit together to make a single ring. Historically, gimmel rings were worn as engagement or wedding rings.
Gold
A bright yellow precious metal that is often alloyed with other metals and used to make jewelry.
Goldsmith
A person who works primarily with gold to create jewelry and other items.
Grade
- Like a grade in school, a rating given to a feature in diamonds or other gems.
- To measure a gem’s special feature (like clarity) using an established grading scale.
Grader
A person who is trained to examine polished diamonds. They grade the gem’s color, clarity, and cut. They also look for signs of treatment done to improve its appearance.
Group
A family of gems made up of several closely related mineral species.
Hairwork
Jewelry made from woven or braided hair. Sometimes used as mourning jewelry to remember a deceased loved one or given as a love token.
Hardness
How well a gemstone resists scratches and scrapes.
Headdress
A decorative or symbolic item of clothing or jewelry worn on the head.
Hieroglyphs
A picture or stylized symbol used to represent a word or a sound. Some ancient peoples, such as the Egyptians and the Mayans, used this as their style of writing.
Hoops
A type of circular earring, made from solid wire or tubing, that dangles below the earlobe.
Huggies
A type of small hoop earring that “hugs” the earlobe and is often hinged on the bottom.
Igneous
Rock formed by the crystallization of molten magma.
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.
Inorganic
A description of something that is made of, or comes from, non-living things.
Insignia
A unique mark, symbol, badge, or emblem that shows the wearer’s rank, status, office, or power.
Inscription
Numbers, marks, or words placed on a polished diamond using a laser, or engraved into metal on a piece of jewelry.
Interpenetrant
When crystals penetrate, or grow through one another, forming another shape such as a star.
Iridescence
A rainbow display that is created when light is broken up into different colors like in a soap bubble or oil slick. It is an optical phenomenon.
Iron
A gray metal that, when refined into steel, is used in jewelry as an alternative to precious metals. The presence of iron in the atomic structure of a gemstone can cause color.
Jadeite
One of two minerals identified as jade. It is brighter and can be more transparent than the other, which is called nephrite . It is usually more rare and valuable than nephrite.
Jewel
A loose gem, such as a pearl or diamond, or a piece of jewelry set with gems.
Jewelry
Decorative items, often made of metal and set with natural, synthetic, or imitation gems, that are used for personal adornment. Items include but are not limited to earrings, rings, necklaces and bracelets.
Karat
A unit of measure for the fineness of gold; abbreviated “k” or “kt.”
Lapidary
- A person who cuts and polishes gem materials other than diamond.
- The art of cutting, polishing, and engraving gems.
- A historical term for a book about the medicinal, magical or mythical characteristics of gemstones.
Lazurite
The mineral in lapis lazuli that makes it blue.
Link (Bracelet)
A type of bracelet with multiple link segments joined together by a flexible joint.
Lore
Facts, traditions, or beliefs about gemstones.
Loupe
A small, portable magnifying lens used for examining gemstones.
Luster
The shine of a gemstone; the way light is reflected off a gemstone’s surface.
Mantle
The layer between the earth’s crust and it’s core.
Matrix
The natural material in which a gem is embedded or the rock in which a gem crystal grows. It can also be the veins of rock which are included in a finished gem such as a turquoise cabochon.
Medallion
A flat piece of metal that features a low-relief design, insignia, or portrait on the front similar to a coin. Medallions are often awarded as a recognition of achievement.
Metallurgy
The study of the physical and chemical properties of metallic elements, their intermetallic compounds, and alloys.
Metalsmith
A person who works with a broad variety of metals to make jewelry, decorative items, or functional objects.
Metamorphic
Rock changed by heat and/or pressure, or by heated liquids from magma.
Miner
A person who extracts ore containing valuable minerals, such as gems or precious metals.
Mineral
A natural, inorganic material with a special chemical composition and crystal structure that repeats itself. Most gems are minerals.
Mineralogist
A person who studies mineralogy.
Mineralogy
The study of minerals.
MohsScale
Used to rank minerals in order of their hardness on a scale of one to ten.
Mojo Bag
A bag containing one or more items, such as gems or other objects, believed to be magical or meaningful to the wearer.
Mollusk
A soft-bodied saltwater or freshwater animal that has one or two shells and no spine. An example is an oyster, a saltwater mollusk that can form pearls.
Mother-of-Pearl
The layer of nacre on the inside of a mollusk’s shell.
Nacre
The smooth, inside surface of a mollusk shell. It is the same material the mollusk uses to form a pearl.
Natural Gems
Gems produced by natural processes, without human help.
Necklace
A piece of jewelry worn around the neck.
Nephrite
One of two minerals identified as jade. It is not as bright and transparent as the other, which is called jadeite.
Octahedron
A crystal shape with eight flat equal sides. Rough diamonds and spinel often form in this shape.
Orb
A sphere that can be either a natural or man-made object. Often used to describe a jeweled ornament that is a symbol of sovereignty.
Organic
A description of something that was made from, or came from, a living or once-living thing.
Panning
A simple way of separating gold, diamonds, or other valuable minerals from the sediment (silt, sand, and gravel) of streams and rivers. The sediment is washed with water in a shallow pan or basket.
Penlight
A portable, handheld light source the size of a pen.
Phenomenon
A special (optical) effect displayed by a gemstone when it interacts with light. Gems with beautiful optical effects are often more valuable.
Platinum
A grayish white precious metal that is often alloyed with other metals and used to make jewelry.
Play-of-Color
The flashing rainbow colors in opal. It is opal’s optical phenomenon.
Pleochroic
Describes a gemstone that displays two or more colors when you look at it from different directions.
Pyrite
The glittery mineral that shows up as flecks and veins in lapis lazuli.
Regalia
Special jewels, clothes, objects, and ornaments that are used as symbols of authority or worn for official ceremonies.
Retailer
A person or business that sells items to consumers. For example, a jewelry retailer would sell jewelry directly to consumers.
Ring
A circular piece of jewelry that is generally worn around the finger.
Rock
A natural material made up of two or more minerals.
Rock Cycle
A constant formation and recycling process that creates new rock from old.
Scepter
A staff or baton carried by a ruler as a symbol of authority for official ceremonies.
Sedimentary
Rock that was created from weathered and eroded remains of older rocks.
Serpentine
A translucent to opaque mineral that can occur in a variety of colors. Serpentine is used as an ornamental or decorative stone and is sometimes set in jewelry.
Signet Ring
A ring that is engraved or is set with an engraved gem featuring a monogram, crest, or symbol of the wearer.
Silver
A bright white precious metal that is often alloyed with other metals and used to make jewelry.
Species
In gemology , a category of gems based on chemical composition and crystal structure .
Stability
How well a gemstone resists the effects of light, heat, and chemicals.
Stone Cloth
Piece of fabric used for cleaning dirt and oil from gems.
Sundial
A device that uses shadows cast by the sun to tell the time of day. Some sundials are circular like a clock, and the shadow’s edge points to the time on the dial’s face.
Synthetic
Manufactured (made) in a laboratory. Gemstones can be synthetic.
Talisman
A charm, gemstone, or ornament believed by some to have special powers, such as bringing the wearer good luck, good health, or good fortune.
Tiara
A woman’s head ornament, often set with gems, worn at formal occasions.
Tie Tack
An ornament on a short pin used to secure a necktie to a shirt.
Timepiece
A clock or watch that tells time without using a striking mechanism.
Tin
A soft bluish-white metal used in pewter, bronze, and some soft solders.
Toadstone
A stone believed to be an antidote for poison during the Middle Ages and the Renaissance. Thought to form in the heads of toads, the stones were actually fossilized teeth from a species of fish.
Torc
A rigid metal ornament, worn around the neck or arm, with an opening which allows it to be placed on the body.
Totem
An object, or a carved or painted depiction of an object, that serves as the symbol or emblem for a group of people and their heritage.
Toughness
How well a gemstone can keep from breaking, chipping, or cracking.
Tweezers
An instrument for holding gemstones.
Twinned Crystal
Crystals that grow in two or more directions that form specific geometric shapes.
Variety
In gemology , a subcategory, or smaller set of species, based on color, transparency, or phenomenon.
Watch Face
The dial or surface of a watch where the time is displayed.
Weathering
The effects of exposure to water, wind, and other environmental conditions.
Zinc
A bluish-white metal that is used in brass, hard solders, and some gold alloys.