Prong setting refers to the use of metal projections or tines, called prongs, to secure a gemstone

Gemstone

A gemstone or gem is a piece of mineral, which, in cut and polished form, is used to make jewelry or other adornments...

 to a piece of jewelry. A prong setting is one component of what is known in the jewelry business as a head, a claw-shaped type of binding (typically 3, 4, or 6 individual prongs per head) that is welded or soldered to a jewelry item in order to mount (or set) a gemstone to the jewelry item. The head can be hand made, cast or die struck, and it is made from some type of precious metal, such as gold

Gold

Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

, silver

Silver

Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...

 and platinum

Platinum

Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is a dense, malleable, ductile, precious, gray-white transition metal...

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Heads used to prong set a gemstone come in a variety of sizes and shapes, depending on the shape of the gemstone, the size of the gemstone, or whether or not the gemstone is facet

Facet

Facets are flat faces on geometric shapes. The organization of naturally occurring facets was key to early developments in crystallography, since they reflect the underlying symmetry of the crystal structure...

ed or cabochon

Cabochon

A cabochon , from the Middle French caboche , is a gemstone which has been shaped and polished as opposed to faceted. The resulting form is usually a convex top with a flat bottom. Cutting en cabochon is usually applied to opaque gems, while faceting is usually applied to transparent stones...

 shaped. Common shapes of heads used in stone setting include round

Brilliant (diamond cut)

A brilliant is a diamond or other gemstone, cut in a particular form with numerous facets so as to have exceptional brilliance. The shape resembles that of a cone and provides maximized light return through the top of the diamond....

, oval, emerald cut, princess cut, marquise cut, pear shaped and trillian cut

Diamond cut

A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut does not refer to shape , but the symmetry, proportioning and polish of a diamond...

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