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Cut & Shape

Facet

/FAS-it/

Definition

A flat, polished surface cut into a gemstone at a precise angle. Facets control how light enters, reflects within, and exits the stone, creating brilliance and fire.

Facets are the fundamental building blocks of gemstone cutting (faceting). Each facet is a flat, polished plane ground into the stone at a calculated angle relative to other facets. The arrangement, number, size, and angles of facets determine the stone's optical performance — how much light is returned (brilliance), how much spectral color is dispersed (fire), and how the stone scintillates when moved (sparkle). A standard round brilliant diamond has 57 or 58 facets, organized into three zones: the table and crown facets (top), the girdle (middle edge), and the pavilion facets (bottom). Faceting is performed on a flat grinding wheel (lap) with the stone held in a dop at precise angles using a faceting machine (handpiece).

Usage in the Trade

Facets are discussed in gemstone grading, cut quality assessment, and jewelry design. Understanding facet arrangement is essential for evaluating diamond cut quality and choosing gemstone shapes.