This quick reference guide contains common diamond and jewelry terminology and their meanings. Use the letter links below to quickly find a diamond or jewelry term.
Adamas: Greek word for indestructible; origin of the word diamond
Antwerp: center for the distribution of rough and polished diamonds; more than half of the world's production of rough, polished, and industrial diamond passes through this city
Appraisal: official valuation document made by a certified gemologist and expert in field of diamonds and metals
Asscher: diamond shape named after the world-renowned cutter Joseph Asscher; square with cut corners
Baguette: rectangular-shaped step cut most commonly used to complement larger diamonds
Bezel: setting in which metal rim secures diamond at the girdle; permits diamond's light-throwing abilities while protecting the stone
Black Diamond: diamond saturated with graphite inclusions
Blemishes: external characteristics (flaws) or surface irregularities
Bourse: diamond-trading markets where members buy and sell goods
Bow-tie Effect: area of less brilliance that appears like a bowtie; occurs in certain fancy-shape diamonds when the stone's proportions are poor
Brilliant-cut: triangular-shaped facets, typically numbering 57, pointed toward the outer part of the diamond
Canary: fancy color diamonds with an intense or vivid yellow color
Carat (ct.): unit of metric measurement used for diamonds; one carat equals .2 grams, or .007 ounces
Certification: a document issued by an independent gemological laboratory that details the vital characteristics of a diamond along with carat, color, clarity, and cut
Channel: setting with uniform diamonds mounted in a grooved channel; diamonds are secured as a group and are not separated by metal as in other setting styles
Clarity: internal and external characteristics of a diamond visible under 10x magnification
Clasp: closure used in bracelets and necklaces for security
Color: rating of the degree of color of a diamond as compared to a master stone(s)
Crown: portion of faceted diamond above the girdle
Crown Angle: relationship of the crown to the girdle; measured in degrees
Culet: small facet polished at the bottom of the pavilion
Cushion: square shape with rounded corners
Cut: refers to diamond shape and/or quality of cut
Cut Grade: GIA rating of polish, symmetry, weight ratio, brightness, scintillation, and fire
Depth: measurement of diamond from the top of the crown to the bottom of the pavilion
Depth Percentage: width ÷ depth = depth°
Diamond: mineral composed entirely of the element carbon
Dispersion: light that shoots through the top of the diamond displaying a color spectrum
Emerald: diamond cut shaped after the way emerald gemstones are cut; shorter in length than a proper rectangle
Facet: flat, polished surface on a diamond
Fancy Color: color in a diamond that increases the stone's value
Fancy Shapes: any shape other than round-cut
Finish: quality of a diamond's polish and symmetry
Fire: light that enters a diamond and is then returned to the viewer
Fluorescence: light emitted from a diamond when the stone is exposed to UV light; often a blue hue
Girdle: band across widest part of a diamond; divides the crown and pavilion
Gold: chemical element Au; most common metal for jewelry because of its beauty and durability
Gold Purity: expressed in karats ('K'). Gold is alloyed with other metals such as silver, copper, zinc, or silicon to produce purities less than 24 carat. Finest gold used in jewelry is 18K (75% pure) or 14K (58.5% pure)
Grain: 1/4 of a carat; 1ct = 4 grains
Grams: unit of weight measurement; used for gold weight
Heart: a pear-cut with two rounded edges instead of one
Hearts and Arrows: ideal-cut symmetrical diamonds will exude arrows when viewed "face up" and hearts when viewed "face down;" can be seen with certainty only under a special microscope
Ideal-cut: polished diamond with exceptional make and light performance
Intensity: concentration of color in fancy color diamond; value is closely tied to a colored diamond's intensity grade
Johannesburg: diamond center in South Africa
Kimberlite: volcanic rock formation in which diamonds are found
Laboratory: facility equipped with scientific tools to verify natural diamonds and grade their characteristics
Laser Inscription: caption on diamond girdle used mostly for identification
Loupe: magnifying glass used in the diamond industry
Make: refers to the craftsmanship of a diamond's cut and finish
Marcel Tolkowsky: published modern diamond cutting method in 1919; known as the originator of the modern brilliant round-cut diamond
Marquise: twice as long as it is wide with pointed ends; named after Marquise de Pompadour's smile
Master Stone: diamond of a predetermined color that is used for comparison in diamond markets and laboratories around the world
Measurements: width1 x width2 x depth (expressed in millimeters)
Mix-cut: diamond cutting method using brilliant-cut and step-cut faceting techniques
Oval: elongated round-cut diamond
Pave': multiple small diamonds set as closely together as possible in two or more rows
Pavilion: portion of faceted diamond below the girdle
Pavilion Angle: relationship of the pavilion to the girdle; measured in degrees
Pear: diamond-cut comprised of the brilliant round-cut and marquise-cuts; resembling tear drop
Platinum: chemical element Pt; silver-white in color and used in its pure form for jewelry
Polish: quality and smoothness of polished diamond surface
Pressure: setting type that uses pressure to hold multiple diamonds in a mounting
Princess: square cut diamond with 90-degree-angled corners
Prong: setting type in which diamonds are held in place by fine metal prongs
Radiant: square to rectangular diamond shape with cut corners
Reflection: immediate reflection of light given off by a diamond's surface
Refraction: light that bounces off the internal wall(s) of the diamond
Report: gemological certificate
Rhodium: process in which gold is dipped in a protective alloy to prevent tarnishing and make the metal white
Rough: any uncut diamond
Round: round-shaped brilliant-cut diamond
Scintillation: reflections from the facets of a diamond seen as the stone is turned in the light
Solitaire: a ring containing a single diamond
Star Facets: triangular facets along the table
Step-cut: rows of elongated facets that act like mirrors
Symmetry: shape and precision of facet arrangement in a diamond
Table: top flat facet of a polished diamond
Table Percentage: comparison of the size of the table facet to the width of the diamond at the girdle in percentage
Tension: setting that uses tension to hold a diamond between fine metal
Trilliant, Triangular: diamond shaped like a triangle
Ultraviolet Light: invisible light waves that can have a positive or negative effect on a diamond's appearance
White Gold: gold mixed with white metals such as silver, palladium, or nickel
Yellow Gold: natural color of pure gold usually mixed with other metals (to dilute purity)
