Jewelry Terms Glossary: 257 Words Explained A to Z

Color, clarity, cut and carat weight: the four factors GIA developed in the 1950s to describe diamond quality in a common language. Each C is graded separately, and together they drive a diamond's appearance and price.

See also: Carat, Clarity, Color, Cut

An alloy of about 41.7 percent gold, stamped 417. It is the lowest karat commonly sold as gold in the US: durable and affordable, with a paler color.

See also: Karat, 14K gold

An alloy of 14/24 gold (about 58.3 percent), commonly stamped 585. It is the most widely used fine-jewelry gold in the US because it balances durability, color and price.

See also: Karat, 18K gold, 10K gold

An alloy of 75 percent gold, stamped 750. It has a richer color than 14K and is a little softer and more costly.

See also: Karat, 14K gold, Fineness

Pure gold, at least 99.9 percent fine in most markets. It has the deepest yellow color but is too soft for most rings that are worn every day. Under the FTC Guides, the word gold used alone, with no karat, should describe only 24K gold.

See also: Karat, 18K gold, Fineness

A milky, bluish light that seems to glide just below the surface of a moonstone as it moves, caused by thin layers of feldspar scattering light.

See also: Moonstone, Play-of-color

The American Gem Society, a US trade organization known for its 0-to-10 diamond grading scale, where 0 is best. AGS Laboratories closed at the end of 2022, and GIA now offers an AGS Ideal report.

See also: GIA, Cut

A saltwater cultured pearl from the Akoya oyster, usually white or cream with rose or silver overtones, typically round and known for sharp, mirror-like luster.

See also: Cultured pearl, Luster

A rare color-change variety of chrysoberyl that looks green to bluish green in daylight and red to purplish red under incandescent light. It is 8.5 on the Mohs scale and a June birthstone.

See also: Color change, Cat's-eye, Birthstone

A blend of metals. Pure gold, silver and platinum are alloyed with other metals to make them harder and, in gold's case, to create yellow, white and rose colors.

See also: Karat, White gold, Rose gold

The purple variety of quartz, 7 on the Mohs scale, and the February birthstone. Long, intense sunlight can slowly fade its color.

See also: Quartz, Citrine, Birthstone

A chain or bracelet worn around the ankle.

See also: Chain

A band, often set with a row of diamonds, given to mark an anniversary or worn alongside an engagement ring.

See also: Eternity band, Wedding band, Stackable rings

Gems associated with wedding anniversary years, such as sapphire for the 5th and 45th, diamond for the 10th and ruby for the 15th and 40th. No single official list exists; GIA publishes a widely used version.

See also: Birthstone, Sapphire

A written estimate of a piece's value by a qualified appraiser, most often its retail replacement value for insurance. It is different from a grading report, which describes quality rather than value.

See also: Grading report, Resale value

The blue to blue-green variety of beryl, 7.5 to 8 on the Mohs scale, and the March birthstone. Most aquamarine is gently heated to remove greenish tones.

See also: Beryl, Birthstone, Heat treatment

The design style of roughly the 1920s and 1930s, known for geometric shapes, strong symmetry, step cuts and crisp platinum work.

See also: Asscher cut, Vintage-inspired, Edwardian

A square step cut with deeply cut corners and a high crown, introduced by the Asscher family of Amsterdam in 1902 and closely tied to Art Deco design.

See also: Emerald cut, Step cut, Art Deco

A star-shaped pattern of light on the surface of a cabochon, caused by aligned needle-like inclusions. It is seen in star sapphire, star ruby and some garnet.

See also: Star sapphire, Cat's-eye, Cabochon

A small, rectangular step-cut stone, often used as side stones or set in rows along a band. Tapered baguettes narrow at one end.

See also: Step cut, Channel setting, Three-stone ring

The loop or fitting at the top of a pendant through which the chain passes. The bail must be large enough for the chain's width and clasp.

See also: Pendant, Chain, Clasp

How wide a band is from edge to edge, measured in millimeters. Wider bands fit more snugly than narrow bands of the same size.

See also: Ring size, Comfort fit

A rigid bracelet, round or oval, that slips over the hand or opens on a hinge.

See also: Cuff bracelet

Stones held between short vertical bars of metal, leaving their sides open to light. It looks like a channel setting with the walls removed.

See also: Channel setting, Eternity band

A pearl with an irregular, non-spherical shape, valued for its organic character and often for strong orient.

See also: Freshwater pearl, Orient

The cage of metal beneath a center stone that joins the prongs and supports the stone, while letting light in from the sides.

See also: Head, Gallery, Prong

The mineral family that includes emerald (green), aquamarine (blue), morganite (pink to peach) and heliodor (yellow). Gem beryls are 7.5 to 8 on the Mohs scale.

See also: Emerald, Aquamarine, Morganite

A rim of metal that surrounds a stone's girdle completely (full bezel) or partly (half bezel). It is among the most secure and snag-free settings, with a clean, modern look.

See also: Prong, Girdle, Flush setting

A gemstone traditionally linked to a month of birth, from garnet for January to turquoise, tanzanite and zircon for December. The modern US list dates to 1912; spinel was added for August in 2016 and tanzanite for December in 2002.

See also: Gemstone, Anniversary gemstones

An opaque black diamond, colored by dense inclusions such as graphite. Most black diamonds in jewelry are color-treated natural diamonds, which should be disclosed.

See also: Fancy color diamond, Treatment, Salt and pepper diamond

A clarity characteristic on the surface of a stone, such as a scratch, nick, polish line or extra facet, as opposed to an inclusion inside it.

See also: Inclusion, Clarity, Polish

A dark, bow-tie-shaped area across the center of some oval, pear, marquise and other elongated brilliant cuts, caused by light leaking out of the pavilion. A slight bow-tie is normal; a strong one is worth avoiding.

See also: Oval cut, Pear cut, Marquise cut

A chain of square links joined to form a smooth, square-section line. It is sturdy and good for pendants.

See also: Chain, Cable chain

An engagement ring and wedding band designed to be worn together, often with matching details.

See also: Wedding band, Contour band

The section of metal beneath the center setting that spans the shoulders and rests above the finger.

See also: Shoulder, Head, Gallery

The white light a polished diamond or gem returns to the eye. A well-cut stone reflects light back up through the top instead of letting it leak out of the pavilion.

See also: Cut, Fire, Scintillation

A faceting style with triangular and kite-shaped facets radiating from the center, designed to maximize sparkle. Round, oval, pear, marquise, princess, cushion and heart are usually brilliant cuts.

See also: Step cut, Mixed cut, Round brilliant

A ring whose two ends pass alongside each other rather than meeting, often holding a stone at each end.

See also: Toi et moi, Shank

A classic chain of uniform oval or round links joined one to the next. Simple and strong, it is the most common pendant chain.

See also: Chain, Rolo chain, Paperclip chain

A stone polished into a smooth dome with no facets. It is the traditional cut for opal, turquoise, moonstone and for star and cat's-eye stones, whose effects only show on a dome.

See also: Star sapphire, Cat's-eye, Opal

The unit of weight for diamonds and gemstones: one carat equals 0.2 grams and is divided into 100 points. Carat is weight, not size, so two stones of the same weight can look different depending on shape and cut. Not to be confused with karat, which measures gold purity.

See also: Point, Total carat weight, Spread, Karat

A single band of light across a cabochon, like the slit of a cat's eye, caused by parallel inclusions. The effect is called chatoyancy and is most prized in chrysoberyl.

See also: Asterism, Cabochon, Alexandrite

A setting in which arches of metal rise from the shoulders to hold the center stone, like the arches of a cathedral. It lifts the stone and adds height and presence.

See also: Shoulder, Solitaire, Head

A flexible line of connected metal links worn as a necklace, bracelet or anklet. Common styles include cable, curb, rope, box, figaro, rolo and wheat, each with its own drape and strength.

See also: Cable chain, Curb chain, Rope chain, Clasp

A row of stones set edge to edge between two parallel walls of metal, with no prongs between them. It protects the stones and gives a smooth, snag-free surface.

See also: Baguette, Eternity band, Bar setting

The yellow to orange variety of quartz, 7 on the Mohs scale, and a November birthstone. Much of the citrine on the market is heat-treated amethyst.

See also: Quartz, Amethyst, Heat treatment

A grade for a diamond's internal inclusions and external blemishes, judged under 10x magnification. GIA's 11 grades run Flawless, Internally Flawless, VVS1, VVS2, VS1, VS2, SI1, SI2, I1, I2 and I3.

See also: Inclusion, Blemish, Eye-clean, Loupe

The fastening that opens and closes a necklace or bracelet, such as a lobster clasp, spring ring, box clasp or toggle.

See also: Lobster clasp, Chain, Bail

A prong shaped into a fine, tapered point that grips the stone with very little visible metal. Double claw prongs pair two slim prongs at each position.

See also: Prong, Solitaire

A tendency of some crystals to split cleanly along flat planes if struck. Diamond and topaz both have perfect cleavage, which is why a hard knock at the wrong angle can chip even a very hard stone.

See also: Toughness, Hardness, Topaz

A group of tiny pinpoint inclusions that can look like a faint haze. Small clouds rarely matter; large, dense ones can soften a diamond's brilliance.

See also: Inclusion, Clarity

A ring with several smaller stones grouped together to create one larger, often floral, shape.

See also: Halo, Floral setting

A large, bold statement ring, usually with a big center gem, made to be noticed.

See also: Halo, Cluster ring

For white diamonds, how close a stone is to colorless. GIA's scale runs from D (colorless) to Z (light yellow, brown or gray) in 23 letter grades, judged against masterstones under controlled lighting. Diamonds with more color than Z are graded as fancy colors.

See also: Colorless, Near colorless, Fancy color diamond, Fluorescence

A gem that looks distinctly different in daylight than in warm indoor light, such as alexandrite (green to red) and some sapphire and garnet.

See also: Alexandrite, Sapphire

The top range of the GIA diamond color scale: D, E and F. These diamonds show no detectable color to a trained grader, and they are the rarest grades in the normal color range.

See also: Color, Near colorless

A band with a rounded inside surface that slides over the knuckle more easily and sits comfortably. Wide comfort-fit bands can feel slightly looser, so some people size down a quarter.

See also: Mens wedding band, Band width, Ring size

Low-grade corundum heavily filled with lead glass, sold more honestly as composite or glass-filled ruby. It is far less durable than ruby and can be damaged by household chemicals or jeweler's heat.

See also: Ruby, Fracture filling, Treatment

A claim that a diamond's sale has not funded armed conflict, usually backed by the Kimberley Process and a supplier's warranty. Lab-grown diamonds avoid mining-related concerns altogether.

See also: Kimberley Process, Lab-grown diamond

A wedding band curved or notched to sit flush against an engagement ring whose head or halo would otherwise leave a gap.

See also: Wedding band, Bridal set

The mineral, aluminum oxide, that forms both ruby and sapphire. Nearly pure corundum is colorless; trace elements such as iron and titanium (blue) or chromium (red and pink) create its colors.

See also: Sapphire, Ruby, Mohs hardness scale

The upper part of a cut stone, above the girdle, including the table and the angled facets around it.

See also: Girdle, Pavilion, Table

A heavy, tightly interlocking curb chain with rounded links that lie flat, popular in men's and statement jewelry.

See also: Curb chain, Chain

A man-made zirconium oxide crystal, usually colorless, widely used as an inexpensive diamond simulant. It is about 8 to 8.5 on the Mohs scale and roughly 65 to 70 percent heavier than a diamond of the same size.

See also: Simulant, Moissanite

A rigid, open-ended bracelet that slides onto the wrist from the side.

See also: Bangle

The point or tiny facet at the bottom of the pavilion. Most modern round brilliants have none or a very small culet; a large culet can look like a dark dot through the table.

See also: Pavilion, Old European cut

A pearl grown after a person places a bead or a piece of tissue inside an oyster or mussel, which then coats it with nacre. Almost all pearls sold today are cultured, and FTC rules require the word cultured.

See also: Natural pearl, Nacre, Akoya pearl, Freshwater pearl

A chain of uniform links twisted so they lie flat. Heavy curb styles include the Cuban link.

See also: Chain, Cuban link chain, Figaro chain

A square or rectangular cut with rounded corners and curved sides, like a pillow. Antique cushions descend from the old mine cut; modern versions are faceted as brilliants for more sparkle.

See also: Old Mine cut, Halo

How well a diamond's proportions, symmetry and polish return light as brightness, fire and scintillation. GIA grades cut from Excellent to Poor, but only for standard round brilliants in the D-to-Z color range. Cut quality is different from shape.

See also: Brilliance, Fire, Scintillation, Diamond shape

Chemical vapor deposition: a method of growing diamond by depositing carbon from a gas, layer by layer, onto a diamond seed plate inside a vacuum chamber. Many CVD diamonds are then HPHT-treated to improve color.

See also: Lab-grown diamond, HPHT, Type IIa

A stone's total depth divided by its average diameter. A diamond that is too deep can face up smaller and darker; one that is too shallow can look glassy.

See also: Table percentage, Spread, Cut

A mineral made essentially of pure carbon crystallized in the cubic (isometric) system. It is 10 on the Mohs scale, the hardest known natural material. Diamonds can be natural or lab-grown; under the FTC Jewelry Guides, a lab-grown diamond must be clearly described with a qualifier such as laboratory-grown.

See also: Natural diamond, Lab-grown diamond, Mohs hardness scale, 4Cs

The outline of a stone seen from above, such as round, oval or emerald. Shape is different from cut, which describes how well the stone is proportioned and finished.

See also: Cut, Round brilliant, Oval cut, Length-to-width ratio

Heating a gem with added chemicals, such as titanium or beryllium, so color penetrates the stone's surface or body. It should always be disclosed because it significantly affects value.

See also: Treatment, Sapphire

The splitting of white light into spectral colors as it passes through a gem. Diamond's dispersion is about 0.044; moissanite's is about 0.104, which is why moissanite shows more colorful fire.

See also: Fire, Moissanite, Refractive index

Assembled stones made of two or three layers glued together, such as a thin slice of opal on a dark backing (doublet) with a clear quartz cap (triplet). They must be disclosed and should not be soaked in water.

See also: Opal, Treatment, Simulant

Earrings with a stone or ornament that hangs below the earlobe; longer, freely moving versions are often called dangle earrings.

See also: Stud earrings, Hoop earrings

An elongated center stone, such as an oval, marquise or emerald cut, set horizontally across the finger instead of pointing toward the fingertip.

See also: Oval cut, Emerald cut, Marquise cut

Jewelry from about 1901 to 1915, named for King Edward VII, known for lacy platinum filigree, milgrain and old European cut diamonds.

See also: Filigree, Milgrain, Old European cut

The green variety of beryl, colored by chromium or vanadium. It is 7.5 to 8 on the Mohs scale but relatively brittle and often included, so it is usually set protectively, and most emeralds are oiled or resin-filled to improve clarity.

See also: Beryl, Oiling, Toughness, Emerald cut

A rectangular step cut with long, parallel facets and cut corners. Instead of brilliant sparkle it shows broad flashes of light, sometimes called a hall-of-mirrors effect, and it shows inclusions and color more readily than brilliant cuts.

See also: Step cut, Asscher cut, Eye-clean

Lettering or decoration cut into metal, by hand or laser. Personalized engraved pieces are typically final sale.

See also: Milgrain, Shank

A band set with a continuous line of matching stones all the way around (full eternity) or across the top (half eternity). Full eternity bands are difficult to resize.

See also: Channel setting, Anniversary band, Resizing

A trade term, not a lab grade, for a diamond with no inclusions visible to the unaided eye at a normal viewing distance. Many VS and some SI diamonds are eye-clean; step cuts such as the emerald cut show inclusions more easily.

See also: Clarity, VS, SI, Step cut

A flat, polished surface on a cut gemstone. A standard round brilliant has 57 or 58 facets, depending on whether it has a culet. Under the FTC Guides, a stone sold simply as a diamond must have at least 17 polished facets.

See also: Table, Crown, Pavilion, Brilliant cut

A natural diamond with distinct color, such as yellow, pink, blue or green, beyond the Z end of the D-to-Z scale. Fancy colors are graded on their own scale, from Faint to Fancy Vivid.

See also: Color, Black diamond

A small crack or fracture inside a diamond that can look white and feathery. Most are harmless, but a large feather that reaches the surface can be a durability concern.

See also: Inclusion, Clarity

A flat chain that alternates several short links with one long link, originally from Italy.

See also: Curb chain, Chain

Delicate openwork made from fine metal wire or pierced metal, forming lacy scrolls, typical of Edwardian and Art Deco jewelry.

See also: Milgrain, Gallery, Edwardian

Precious-metal purity in parts per thousand: 585 for 14K gold, 750 for 18K, 925 for sterling silver and 950 for platinum.

See also: Hallmark, Karat, Sterling silver, Platinum

Flashes of spectral color as a stone moves, caused by dispersion splitting white light into its colors. Fire and brilliance together are what most people call sparkle.

See also: Dispersion, Brilliance, Scintillation

The highest clarity grade: no inclusions and no blemishes visible to a skilled grader at 10x magnification. Internally Flawless (IF) allows minor surface blemishes only. The FTC Jewelry Guides restrict the word flawless to stones that meet this 10x standard.

See also: Clarity, VVS, Loupe

A design in which stones or metal form petals, leaves or vines around a center stone, a hallmark of nature-inspired and vintage-style rings.

See also: Cluster ring, Halo, Filigree

A glow, usually blue, that some diamonds show under ultraviolet light. GIA reports it as None, Faint, Medium, Strong or Very Strong. About 25 to 35 percent of diamonds fluoresce, and GIA describes it as neither good nor bad.

See also: Color, Grading report

A stone sunk into a drilled hole so its table sits level with the metal surface. It is very protective and popular for men's bands and minimal designs.

See also: Bezel, Mens wedding band

Filling cracks in a diamond or other gem with a glass-like substance to hide them. It is not permanent, can be damaged by heat or ultrasonic cleaning, and must be disclosed.

See also: Treatment, Composite ruby, Ultrasonic cleaner

A cultured pearl grown in freshwater mussels, mostly in China. It comes in many shapes and soft natural colors and is more affordable because one mussel can grow many pearls.

See also: Cultured pearl, Baroque pearl

US Federal Trade Commission rules (16 CFR Part 23) on how jewelry may be described in marketing, covering terms such as diamond, lab-grown, gold, platinum, cultured pearl and treatment disclosure.

See also: Lab-grown diamond, Treatment, Karat

The metalwork under the head of a ring, visible from the side. It can be plain or decorated with filigree, scrolls or a hidden halo.

See also: Basket, Hidden halo, Filigree

A family of related minerals rather than one stone, from the classic deep red of almandine and pyrope to orange spessartite and green tsavorite and demantoid. Garnets range from about 6.5 to 7.5 on the Mohs scale; red garnet is the January birthstone.

See also: Birthstone, Asterism

A mineral, rock or organic material that is cut and polished for jewelry because of its beauty, durability and rarity. Under the FTC Guides, a lab-made stone must not be called a gem or gemstone without a clear qualifier such as laboratory-created.

See also: Precious and semi-precious, Birthstone, Lab-created gemstone

Where a natural gem was mined, such as Kashmir, Sri Lanka (Ceylon), Madagascar or Montana for sapphire. Some origins carry a premium, and labs can sometimes determine origin from a stone's inclusions and chemistry.

See also: Sapphire, Grading report

The Gemological Institute of America, a nonprofit founded in 1931 that created the 4Cs and the D-to-Z color scale. Since October 1, 2025, GIA describes D-to-Z lab-grown diamonds as Premium or Standard instead of using its natural-diamond color and clarity grades.

See also: Grading report, 4Cs, Lab-grown diamond

The narrow band around the widest part of a cut stone, where the crown meets the pavilion. Settings usually grip the stone at the girdle, and lab inscriptions are lasered onto it.

See also: Crown, Pavilion, Laser inscription

A thin layer of gold applied to another metal, usually by electroplating. In the US, gold electroplate means at least 0.175 microns of 10K or better gold, and heavy gold electroplate at least 2.5 microns; plating wears with use.

See also: Gold-filled, Vermeil, Rhodium plating

A base-metal core with a layer of at least 10K gold mechanically bonded to it, making up at least one-twentieth of the article's metal weight. It is far thicker than plating but is not solid gold.

See also: Gold plating, Vermeil

A document from an independent gem lab, such as GIA or IGI, that describes a stone's identity, measurements and quality grades. It is often called a certificate, but it is an expert assessment, not an appraisal or a guarantee of value.

See also: GIA, IGI, Appraisal, Laser inscription

Marks stamped on precious metal to show its purity, such as 14K, 585, 750, 925 or PLAT. In the US, a quality mark on gold or silver must be accompanied by the maker's registered trademark.

See also: Fineness, Karat, Sterling silver

A ring of small diamonds or gems surrounding a center stone, making it look larger and adding sparkle. A double halo adds a second ring.

See also: Hidden halo, Pavé, Cushion cut

A material's resistance to scratching, measured for gems on the Mohs scale. Everyday dust contains quartz (7), which slowly dulls softer gems; it is not the same as toughness.

See also: Mohs hardness scale, Toughness, Cleavage

The part of a mounting that holds the center stone, made up of the prongs or bezel and the structure beneath. Heads are sized and shaped for a specific stone.

See also: Prong, Basket, Mounting

A brilliant cut in the outline of a heart. Good symmetry between the two lobes and a well-defined cleft matter most; very small hearts can lose their outline.

See also: Brilliant cut, Bow-tie effect

A pattern of eight hearts (seen from the pavilion) and eight arrows (seen from the crown) visible through a special viewer in round brilliants cut with very precise optical symmetry.

See also: Symmetry, Round brilliant, Cut

Controlled heating to improve a gem's color or clarity. It is common, permanent and widely accepted for sapphire, ruby, aquamarine, tanzanite and citrine, and is still disclosed as part of good practice.

See also: Treatment, Sapphire, Tanzanite

A flat chain of slanted links that lie in a smooth, liquid V-pattern. It is elegant but can kink, so store it flat.

See also: Chain

A row of small stones set around the base of the center stone's head, visible mainly from the side, adding sparkle without changing the ring's top view.

See also: Halo, Gallery, Solitaire

Earrings shaped as a circle or oval, from tiny huggies to large statement hoops.

See also: Huggie earrings, Drop earrings

High pressure, high temperature. The term covers two things: a way to grow diamonds from carbon under conditions like those deep in the earth, and a treatment that can change or improve the color of natural or lab-grown diamonds. Treated stones should be disclosed.

See also: Lab-grown diamond, CVD, Treatment

The three parts of a gemstone's color: hue is the basic color (blue, green), tone is how light or dark it is, and saturation is its strength or purity. The most valued colored gems usually combine a pure hue, medium to medium-dark tone and strong saturation.

See also: Sapphire, Color

Small, thick hoops that hug the earlobe closely, usually with a hinged closure.

See also: Hoop earrings, Stud earrings

A loose marketing term for materials less likely to cause skin reactions. In fine jewelry it usually means platinum, palladium, titanium, high-karat gold or nickel-free white gold; it is not a medical guarantee.

See also: Nickel, Platinum, Titanium

The International Gemological Institute, a gem lab founded in Antwerp in 1975 that grades large numbers of lab-grown diamonds and continues to use the 4Cs scales for both natural and lab-grown stones.

See also: GIA, Grading report, Lab-grown diamond

A bead coated to look like a pearl, such as glass or shell-based beads. Under FTC rules it must be described as imitation, artificial or simulated.

See also: Cultured pearl, Simulant

The lowest clarity grades, I1, I2 and I3. Inclusions are obvious at 10x and may affect transparency, brilliance or durability.

See also: Clarity, SI

A clarity characteristic inside a stone, such as a crystal, feather, cloud or needle, formed as it grew. Inclusions work like a fingerprint and are the main factor in a clarity grade.

See also: Clarity, Blemish, Feather, Cloud

Exposing a gem to radiation to change its color, as in nearly all blue topaz and some colored diamonds. Commercial irradiated gems are checked for safety before sale.

See also: Treatment, Topaz, London blue topaz

A name shared by two different minerals: jadeite (about 6.5 to 7 on the Mohs scale) and nephrite (about 6 to 6.5). Both are exceptionally tough, so jade resists breaking far better than its hardness suggests.

See also: Toughness, Hardness

A small metal ring used to join parts of a piece, such as a clasp to a chain or a charm to a bracelet.

See also: Clasp, Bail

A measure of gold purity in 24ths. 24K is pure gold, 18K is 75 percent gold, 14K is 14/24 or about 58.3 percent (commonly stamped 585), and 10K is about 41.7 percent. Higher karat is richer in color but softer.

See also: 14K gold, 18K gold, Alloy, Carat

An international certification scheme launched in 2003 to stop rough diamonds that fund armed conflict from entering the legitimate trade. Critics note its narrow definition of conflict diamonds.

See also: Conflict-free, Natural diamond

A stone grown in a laboratory with essentially the same chemistry, crystal structure and properties as its natural counterpart, such as lab-created sapphire, ruby, emerald or alexandrite. FTC rules require a qualifier such as laboratory-created, laboratory-grown or synthetic.

See also: Lab-grown diamond, Simulant, Gemstone

A real diamond grown in a laboratory by the HPHT or CVD method, with essentially the same chemical, physical and optical properties as a natural diamond. The FTC requires a clear qualifier such as laboratory-grown or laboratory-created. In The Knot's 2026 study, 61 percent of engagement rings had a lab-grown center stone.

See also: Natural diamond, CVD, HPHT, Simulant

A deep blue rock made mostly of lazurite, often flecked with golden pyrite. It is about 5 to 5.5 on the Mohs scale and the traditional ninth-anniversary gem.

See also: Anniversary gemstones, Cabochon

A long necklace without a conventional clasp that is looped or slipped through itself, often ending in a drop or Y shape.

See also: Necklace lengths, Chain

A microscopic number or message lasered onto a diamond's girdle, usually matching its grading report number. GIA inscribes lab-grown diamonds it assesses with "Laboratory-Grown" and the report number.

See also: Girdle, Grading report

An elongated stone's length divided by its width. Ovals often fall around 1.30 to 1.50 and marquises around 1.75 to 2.25; the right ratio is a matter of taste.

See also: Oval cut, Marquise cut, Pear cut, Diamond shape

A secure, claw-shaped clasp with a spring-loaded lever, the most common fastening on fine chains.

See also: Clasp, Jump ring

Trade name for topaz in a deep, slightly grayish blue, created by irradiating and heating colorless topaz. The color is stable in normal wear.

See also: Topaz, Irradiation

A small hand magnifier, standardized at 10x for grading, used by jewelers and gemologists to inspect stones and settings.

See also: Clarity, Inclusion, Eye-clean

The brightness and sharpness of light reflected from a pearl's surface and from within its nacre. It is one of the most important factors in pearl value.

See also: Nacre, Overtone, Orient

A piece crafted after you order it, often in your chosen metal, stone and size, rather than shipped from finished stock.

See also: Semi-mount, Ring size

A long, boat-shaped brilliant with two pointed ends. It has one of the largest face-up sizes per carat and lengthens the look of the finger; the points are best protected by V-prongs.

See also: Pear cut, Bow-tie effect, V-prong

A wedding band designed for men, typically wider (often 5 to 8 mm) and in gold, platinum or alternative metals, with or without stones.

See also: Wedding band, Comfort fit, Flush setting

Pavé setting with very small accent stones, often set under magnification, for a fine, continuous line of sparkle.

See also: Pavé, Halo

A border of tiny metal beads along an edge, made with a knurling tool, that adds a soft, antique texture typical of vintage designs.

See also: Filigree, Vintage-inspired, Edwardian

A stone that combines brilliant and step faceting, such as a radiant cut or many colored gemstones with a brilliant crown and step-cut pavilion.

See also: Brilliant cut, Step cut, Radiant cut

A 1-to-10 ranking of scratch resistance devised by Friedrich Mohs in 1812, from talc (1) to diamond (10). It is a ranking, not a linear measure: diamond is far harder than corundum (9) in absolute terms. Stones at 8 and above suit everyday rings.

See also: Hardness, Toughness, Cleavage

Silicon carbide, a gem first found in tiny amounts in a meteorite crater and now made in laboratories for jewelry. It is about 9.25 on the Mohs scale and shows more fire than diamond (dispersion about 0.104 versus 0.044). Moissanite is its own gem, not a lab-grown diamond.

See also: Dispersion, Simulant, Lab-grown diamond

A feldspar gem, about 6 to 6.5 on the Mohs scale, with a soft, floating sheen called adularescence. So-called rainbow moonstone is a white labradorite with blue and multicolor flashes. A June birthstone.

See also: Adularescence, Cabochon, Birthstone

The pink to peach variety of beryl, colored by manganese and named after the financier J.P. Morgan. It is 7.5 to 8 on the Mohs scale and often heated to improve its pink.

See also: Beryl, Aquamarine

A ring set with the birthstones of a mother's children, often in a row or cluster.

See also: Birthstone, Stackable rings

The iridescent nacre lining a mollusk shell, cut and polished for inlays, beads and dials.

See also: Nacre, Natural pearl

The metal framework of a ring or other piece, without its center stone.

See also: Semi-mount, Setting, Head

The iridescent layers of aragonite and protein that a mollusk deposits to form a pearl, also called mother-of-pearl when it lines a shell. Thicker nacre generally means better luster and durability.

See also: Luster, Cultured pearl, Mother-of-pearl

A diamond that formed deep in the earth, typically between one and three and a half billion years ago, and was carried toward the surface by volcanic eruptions. It has the same chemistry and hardness as a lab-grown diamond; the difference is origin, which a gem lab can identify.

See also: Diamond, Lab-grown diamond, Kimberley Process

A pearl formed by a mollusk without human help. Natural pearls are now very rare; under the FTC Guides, the word pearl alone refers to a natural pearl.

See also: Cultured pearl, Nacre

The G, H, I and J grades on the GIA color scale. They show slight warmth that is often not noticeable to the untrained eye once set, which makes them a popular balance of appearance and value.

See also: Color, Colorless

Common women's necklace lengths are about 16 inches (choker to collarbone), 18 inches (just below the collarbone, the most popular pendant length) and 20 to 24 inches for layering or a lower drop.

See also: Chain, Pendant, Lariat

A metal used in some white gold alloys and the most common cause of metal allergy in jewelry. Nickel-free choices include platinum, palladium and palladium-alloyed white gold.

See also: White gold, Hypoallergenic, Palladium

Filling surface-reaching fissures in emerald with colorless oil or resin to make them less visible. It is traditional and very common but not permanent, so oiled emeralds should avoid ultrasonic and steam cleaners.

See also: Emerald, Treatment, Ultrasonic cleaner

An antique round diamond, common from about the 1890s to the 1930s, with a small table, tall crown and open culet. It is the forerunner of the modern round brilliant and prized in antique jewelry.

See also: Old Mine cut, Round brilliant, Culet

An antique cushion-shaped diamond cut by hand, mainly in the 18th and 19th centuries, with a small table, high crown and large culet. It glows with broad, soft flashes.

See also: Old European cut, Cushion cut, Culet

A banded variety of chalcedony quartz, 6.5 to 7 on the Mohs scale. The solid black onyx used in jewelry is almost always dyed chalcedony, a long-accepted treatment.

See also: Quartz, Treatment

A gem made of tiny silica spheres and water, famous for play-of-color, the shifting flashes of spectral color. It is 5.5 to 6.5 on the Mohs scale, so it is best in protective settings and occasional-wear rings. October birthstone.

See also: Play-of-color, Doublet and triplet, Cabochon

A soft, shifting iridescence just below a pearl's surface, caused by light passing through its nacre layers; it is most visible in fine natural and baroque pearls.

See also: Overtone, Luster

An elongated brilliant cut that keeps a round's sparkle in a softer outline and faces up larger than a round of the same weight. It was the second most chosen center shape (25 percent) in The Knot's 2026 study, and the top shape for lab-grown rings.

See also: Bow-tie effect, Length-to-width ratio, Spread

A translucent secondary color that seems to float over a pearl's body color, such as rose, silver or green.

See also: Luster, Orient

A rare sapphire with a delicate blend of pink and orange, named after the Sinhalese word for the lotus blossom. It is one of the most collectible sapphire colors.

See also: Sapphire, Corundum

A naturally white metal in the platinum family, lighter than platinum and hypoallergenic. It is used on its own (usually 950) and as a nickel-free whitener in white gold.

See also: Platinum, White gold, Platinum group metals

A chain of long, flat, rectangular links shaped like paper clips, a modern layering favorite.

See also: Cable chain, Chain

The soft satin finish metals such as platinum develop as fine scratches accumulate with wear. Some people love it; a jeweler can polish it back to a high shine.

See also: Platinum, Tarnish

The lower part of a cut stone, below the girdle. Its angles act like mirrors: correct angles send light back up through the crown, while angles that are too steep or too shallow let light escape.

See also: Crown, Culet, Brilliance

From the French for paved: many small stones set close together and held by tiny beads of metal, so the surface looks covered in sparkle. Micro-pavé uses especially small stones.

See also: Micro-pavé, Halo, Total carat weight

A teardrop-shaped brilliant, rounded at one end and pointed at the other. It is usually worn with the point toward the fingertip.

See also: Marquise cut, Bow-tie effect

An ornament that hangs from a chain, attached by a bail. Many pendants are sold with a matching chain.

See also: Bail, Chain

The yellowish green gem variety of the mineral olivine, 6.5 to 7 on the Mohs scale, and an August birthstone. Its color comes from iron and is rarely treated.

See also: Birthstone

A naturally white, dense precious metal, about 95 percent pure in most jewelry and roughly 60 percent heavier than 14K white gold. It is hypoallergenic and never needs re-plating. On the Vickers scale it is softer than 14K white gold, but scratches displace the metal rather than remove it, so it develops a patina instead of thinning.

See also: White gold, Patina, Palladium

Six related metals: platinum, palladium, rhodium, ruthenium, iridium and osmium. In jewelry, platinum and palladium are used as metals and rhodium as plating; some platinum alloys contain ruthenium or iridium.

See also: Platinum, Palladium, Rhodium plating

The flashes of rainbow color that move across precious opal as it turns, caused by light diffracting through its orderly silica spheres.

See also: Opal, Adularescence

The property of some gems to show different colors when viewed from different directions. Tanzanite, tourmaline and sapphire can be strongly pleochroic, which cutters use to orient the best color face-up.

See also: Tanzanite, Tourmaline, Sapphire

One hundredth of a carat. A 0.50 carat diamond is often called a 50-pointer. Points let jewelers describe small stones precisely, especially accent diamonds.

See also: Carat, Total carat weight

A grade for the smoothness of a diamond's facet surfaces, from Excellent to Poor on GIA reports. Polish is graded for every shape.

See also: Symmetry, Cut, Blemish

Old trade labels in which diamond, ruby, sapphire and emerald were called precious and other gems semi-precious. The split says nothing reliable about value, since a fine tsavorite can cost more than a low-grade ruby, and the FTC calls either term misleading for lab-made stones.

See also: Gemstone, Sapphire, Ruby, Emerald

A square or slightly rectangular brilliant with sharp, pointed corners. It sparkles strongly and has a modern outline; its corners are best protected by prongs that cover them.

See also: Brilliant cut, V-prong

A ring given as a symbol of commitment before an engagement, usually simpler and smaller than an engagement ring.

See also: Solitaire, Stackable rings

A small metal claw that holds a stone. Four or six prongs are the most common way to hold a center stone, lifting it into the light with minimal metal; prong tips wear with time and can be re-tipped.

See also: Claw prong, V-prong, Basket, Re-tipping

One of the most common minerals on earth, 7 on the Mohs scale. Gem varieties include amethyst, citrine, rose quartz and smoky quartz, and the microcrystalline forms called chalcedony include onyx and agate.

See also: Amethyst, Citrine, Onyx, Hardness

A square or rectangular cut with trimmed corners and brilliant faceting on the crown and pavilion, combining a step-cut outline with a brilliant's sparkle. It was created by Henry Grossbard in 1977.

See also: Emerald cut, Princess cut, Mixed cut

Adding new metal to worn prong tips so they hold a stone securely again. It is routine maintenance for rings worn every day.

See also: Prong, Setting

A measure of how much a gem bends light, used by gemologists to identify stones. Diamond's is about 2.42; higher numbers generally mean more brilliance.

See also: Dispersion, Brilliance

What a piece might sell for secondhand, usually well below its retail price or insurance replacement value.

See also: Appraisal

Making a ring larger or smaller by cutting the shank and adding or removing metal. Most gold and platinum rings can be resized by a size or two; eternity bands, tension settings, tungsten and some titanium rings usually cannot.

See also: Ring size, Shank, Eternity band

A very thin coating of rhodium, a bright, hard platinum-group metal, applied over white gold (and sometimes silver) for a cool white finish. It wears gradually and is re-applied during routine service.

See also: White gold, Platinum group metals

A measure of finger circumference on a numbered scale; the US uses numbers in quarter and half steps, while the UK and other countries use letters or millimeters. Fingers swell with heat and shrink with cold, so measure at a normal temperature.

See also: Resizing, Comfort fit, Band width

A chain of round, uniform links, similar to a cable chain but with thicker, rounder links. Also called a belcher chain.

See also: Cable chain, Chain

A chain of small links woven in a spiral so it resembles a twisted rope, catching light along its length.

See also: Chain, Wheat chain

An antique cut with a flat base and a domed top covered in triangular facets. It gives a soft, glowing shimmer rather than sharp sparkle and is popular again in vintage-inspired designs.

See also: Old European cut, Cabochon

Gold alloyed with a higher share of copper for a warm pink color. It needs no plating, and the copper makes it one of the tougher gold alloys.

See also: Yellow gold, Alloy

A diamond or gem crystal in its natural, uncut state, before it is planned, cut and polished.

See also: Facet, Natural diamond

A circular diamond with 57 or 58 facets arranged for maximum brilliance. It is the only shape GIA gives an overall cut grade, and in The Knot's 2026 Real Weddings Study round was the most chosen center-stone shape (26 percent).

See also: Brilliant cut, Hearts and arrows, Solitaire

The red variety of corundum, colored by chromium. Like sapphire it is 9 on the Mohs scale. Heating is common and widely accepted; lead-glass-filled composite ruby is a different, far less durable product that must be disclosed.

See also: Corundum, Sapphire, Composite ruby, Heat treatment

A natural diamond with many visible black and white inclusions, chosen for its speckled, one-of-a-kind look rather than for high clarity.

See also: Inclusion, Black diamond, Clarity

Gem-quality corundum in any color except red, which is ruby. Blue is the classic, but sapphire also occurs in pink, yellow, green, white, purple and the pink-orange padparadscha. It is 9 on the Mohs scale; among natural gems, only diamond is harder.

See also: Corundum, Ruby, Padparadscha, Geographic origin

The sparkle and the pattern of light and dark areas that play across a stone as it, the light or the viewer moves.

See also: Brilliance, Fire, Facet

A finished mounting, often with its accent stones already set, made ready to receive a center stone chosen separately.

See also: Mounting, Head

The way a stone is held in jewelry, and the metalwork that holds it. The setting affects security, how much light reaches the stone, how high it sits and the whole character of a ring.

See also: Prong, Bezel, Mounting, Head

The band of a ring, the part that circles the finger. It may be plain, tapered, split, twisted or set with stones, and it is where a ring is cut and rejoined when resized.

See also: Shoulder, Head, Split shank, Resizing

The upper part of the shank on each side of the center stone, often set with accent stones or shaped into a cathedral arch.

See also: Shank, Cathedral setting

Slightly Included, graded SI1 and SI2. Inclusions are noticeable at 10x and are sometimes visible without magnification, depending on their size and position, so SI stones are best judged individually.

See also: Clarity, VS, Included (I), Eye-clean

A material that imitates the look of another gem but has different chemistry and properties, such as cubic zirconia or glass imitating diamond. Under FTC rules it must be described as imitation or simulated.

See also: Cubic zirconia, Moissanite, Lab-created gemstone

A ring with one center stone and no other prominent stones on top. It is the most classic engagement ring style; in The Knot's 2026 study, 38 percent of engagement rings were solitaires.

See also: Prong, Round brilliant, Cathedral setting

A large saltwater cultured pearl from the white-lip or gold-lip oyster, grown mainly in Australia, Indonesia and the Philippines, in white, silver and golden tones. Among the largest and most valuable cultured pearls.

See also: Tahitian pearl, Luster

A durable gem, 8 on the Mohs scale, found in red, pink, blue, purple and gray. Some famous historic rubies, including the Black Prince's Ruby in the British Imperial State Crown, are actually spinel. It was added as an August birthstone in 2016.

See also: Ruby, Birthstone

A band that divides into two strands as it approaches the center stone, adding width and visual interest without extra weight.

See also: Shank, Shoulder

How large a diamond looks from the top, measured as its face-up diameter or length and width. A shallow, well-proportioned stone spreads larger than a deep one of the same weight; elongated shapes such as oval and marquise tend to face up larger per carat than a round.

See also: Carat, Depth percentage, Oval cut

Impregnating a porous gem, most often turquoise, with resin or plastic to harden it and improve its color.

See also: Turquoise, Treatment

Slim rings designed to be worn several at a time, mixing metals, stones and textures.

See also: Anniversary band, Wedding band

A sapphire cut as a cabochon that shows a six-rayed star gliding across its dome, an effect called asterism, caused by fine needle-like inclusions.

See also: Sapphire, Cabochon, Asterism

Cleaning jewelry with a jet of pressurized steam. It suits hard, untreated stones in sturdy settings but not heat-sensitive, porous or oiled gems.

See also: Ultrasonic cleaner, Oiling

A faceting style with long, straight facets parallel to the girdle in rows, like stairs. Step cuts such as emerald, Asscher and baguette show clarity and color more readily and give broad flashes rather than pinpoint sparkle.

See also: Brilliant cut, Emerald cut, Asscher cut, Baguette

An alloy of at least 92.5 percent silver, usually with copper, stamped 925. It is bright and affordable but softer than gold and tarnishes over time.

See also: Fineness, Vermeil, Tarnish

Earrings with a single stone or ornament that sits on the earlobe, fastened with a post and back. Screw backs add security for valuable studs.

See also: Huggie earrings, Drop earrings

A grade for how precisely a diamond's facets are shaped, aligned and placed, from Excellent to Poor on GIA reports. Fancy shapes receive polish and symmetry grades even though GIA does not give them a cut grade.

See also: Polish, Cut, Hearts and arrows

The large flat facet on top of a cut stone. Table percentage, its width compared with the stone's average diameter, is one of the proportions used in cut grading.

See also: Crown, Table percentage, Facet

The width of the table facet divided by the stone's average diameter. It is one of the proportions, with depth and angles, that determine a round diamond's cut grade.

See also: Table, Depth percentage, Cut

A saltwater cultured pearl from the black-lip oyster in French Polynesia, with naturally dark body colors from gray to black and overtones such as green, peacock and aubergine.

See also: South Sea pearl, Overtone

A blue-violet variety of the mineral zoisite found commercially only in Tanzania, discovered in 1967. It is about 6 to 7 on the Mohs scale, is almost always heat-treated, and became a December birthstone in 2002.

See also: Pleochroism, Heat treatment, Birthstone

A dark surface film that forms when silver (and low-karat gold alloys) react with sulfur in the air, skin or household products. It polishes away and is not damage to the metal.

See also: Sterling silver, Patina

A flexible bracelet set with a continuous line of matching diamonds or gems, a name popularly traced to tennis player Chris Evert, who paused a match to look for hers.

See also: Tennis necklace, Eternity band, Clasp

A necklace set with a continuous line of matching diamonds or gems, the necklace version of the tennis bracelet.

See also: Tennis bracelet

A modern setting in which the stone appears to float, held by the spring pressure of the band's two ends. It needs precise engineering and is very difficult to resize.

See also: Bezel, Resizing

A center stone flanked by two side stones, often said to represent past, present and future. The sides may be matching diamonds, pears, baguettes, trillions or colored gems.

See also: Baguette, Trillion, Toi et moi

A light, strong, hypoallergenic metal used mostly in men's bands. It is difficult or impossible to resize properly.

See also: Tungsten carbide, Hypoallergenic, Resizing

French for you and me: a two-stone ring in which a pair of stones, often different shapes or gems, sit side by side, symbolizing two people joined.

See also: Three-stone ring, Bypass ring

A hard gem, 8 on the Mohs scale, with perfect cleavage that can make it chip if struck. Natural topaz is often colorless, pale blue or golden; the vivid Swiss blue and London blue topaz in jewelry are produced by irradiation and heating.

See also: London blue topaz, Cleavage, Irradiation

The combined weight of every diamond or gemstone in a piece, abbreviated TCW or CTW. A ring described as 1 ct TW may hold one large stone or many small ones, so check how much of the weight is in the center stone.

See also: Carat, Point, Pavé

A gem's resistance to chipping and breaking, separate from hardness. Jade is very tough despite a modest Mohs number, while emerald is hard but relatively brittle.

See also: Hardness, Cleavage, Jade

A gem family, 7 to 7.5 on the Mohs scale, with the widest color range of any gem, including pink, green, blue and two-color watermelon tourmaline. It is an October birthstone.

See also: Birthstone, Pleochroism

Any process other than cutting and polishing that improves a gem's appearance or durability, such as heating, oiling, filling, irradiation, diffusion or coating. The FTC requires disclosure when a treatment is not permanent, needs special care, or significantly affects value.

See also: Heat treatment, Oiling, Fracture filling, Irradiation

A triangular cut, usually with slightly curved sides, used as side stones beside a center stone or on its own as a bold center.

See also: Three-stone ring, Brilliant cut

A very hard, scratch-resistant tungsten compound used for men's bands. It cannot be resized and can crack under a sharp impact, which is also how it is removed in an emergency.

See also: Titanium, Resizing

An opaque blue to green mineral, about 5 to 6 on the Mohs scale, valued since antiquity. Much turquoise is stabilized with resin to harden it and deepen color, a treatment that should be disclosed. A December birthstone.

See also: Stabilization, Cabochon, Birthstone

A piece that combines two metal colors, such as a yellow gold band with a white gold head, often used so a colorless diamond sits in white metal.

See also: Yellow gold, White gold, Head

A scientific diamond type with almost no nitrogen. It is a small share of natural diamonds and is common among CVD lab-grown diamonds, so it is one of the clues labs use when testing origin.

See also: Lab-grown diamond, CVD, Natural diamond

A machine that cleans jewelry with high-frequency vibrations in liquid. It is safe for most solid gold or platinum set with untreated diamond, sapphire or ruby, but can damage emerald, opal, pearl, tanzanite, turquoise and fracture-filled stones.

See also: Steam cleaning, Oiling, Fracture filling

A V-shaped prong that covers and protects a pointed corner or tip, such as the points of a marquise, pear or princess cut.

See also: Prong, Marquise cut, Princess cut

Sterling silver coated with gold of at least 10K, with a minimum thickness equal to 2.5 microns of fine gold under the FTC Guides. It gives a gold look at lower cost, but the coating can wear through.

See also: Sterling silver, Gold plating, Gold-filled

Jewelry from Queen Victoria's reign (1837 to 1901), ranging from romantic gold designs with colored gems to mourning jewelry, often set with rose cut and old mine cut diamonds.

See also: Rose cut, Old Mine cut, Vintage-inspired

A new piece designed in the style of an earlier era, with details such as milgrain, filigree or engraving. It differs from antique (generally 100 or more years old) and estate (previously owned) jewelry.

See also: Milgrain, Filigree, Art Deco, Edwardian

Very Slightly Included, graded VS1 and VS2. Inclusions are difficult (VS1) to somewhat easy (VS2) to see at 10x and are usually not visible face-up to the unaided eye in brilliant-cut diamonds.

See also: Clarity, VVS, SI, Eye-clean

Very, Very Slightly Included, graded VVS1 and VVS2. The inclusions are so minute that they are extremely difficult (VVS1) to very difficult (VVS2) for a trained grader to see at 10x, and invisible to the unaided eye.

See also: Clarity, VS, Flawless (FL)

The ring exchanged at the wedding ceremony, plain or set with stones, usually worn with the engagement ring.

See also: Bridal set, Contour band, Eternity band

A chain of twisted oval links woven together so it looks like a stalk of wheat; strong and flexible.

See also: Rope chain, Chain

Gold alloyed with white metals such as palladium, nickel, silver or zinc, almost always finished with rhodium plating for a bright white look. The plating thins with wear, typically over one to three years, and a jeweler re-plates it.

See also: Rhodium plating, Platinum, Nickel

Colorless sapphire, natural or lab-created, sometimes chosen as a diamond alternative. It is 9 on the Mohs scale but shows less brilliance and fire than diamond or moissanite.

See also: Sapphire, Simulant

Gold alloyed mainly with copper and silver to keep its warm color while adding strength. In The Knot's 2026 study, yellow gold was the most chosen engagement ring metal at 39 percent.

See also: Karat, White gold, Rose gold