Brilliance: Internal and external reflection of white light to the eye from a gemstone
Carat-weight: Standard measurement for diamond size
Clarity: The degree to which tiny marks of nature called inclusions are present in the diamond.
Colour: Diamonds range from colourless – the rarest and most valuable – to yellowish, with a spectrum of shadings in between.
Comparison stones: A set of laboratory colour-calibrated master stones used for proper colour grading
Crown: Top part of the diamond above the girdle
Cut: Not to be confused with the shape of a diamond, cut refers to the arrangement of a diamond’s facets. A diamond which is “ideal cut” captures and releases the maximum play of light.
Facet: Polished surface on a diamond
Flawless: Diamond without external or internal blemishes or inclusions seen under 10x magnification
Fire: Flashes of different rainbow colours resulting from the dispersion of light
G.I.A.: Gemological Institute of America – the leading independent trade laboratory
Gemologist: One who has successfully completed recognised courses of study in gem identification, grading and pricing, as well as diamond grading and appraising.
Girdle: Circumference of a diamond, which is usually held by prongs of a setting and separates the crown and pavilion
Inclusions: Natural impurities in a diamond, which were formed during the crystallisation process.
Loupes: Jewellers’ eyepieces used for magnification
Pavilion: The bottom part of the diamond below the girdle
Shape: Not to be confused with cut, shape means the geometric form of the stone. Popular shapes include the round brilliant, marquise, emerald cut, pear, oval and many others.
Sparkle: Flashing effect produced when a diamond is moved in the light.
Table: Top, largest and most important facet in a diamond
