A peg head is a pre-fabricated prong-setting head — basket, crown, or simple cup with claws — manufactured with an integral cylindrical peg on its underside, intended to be inserted into a drilled hole in a ring shank or other mount and soldered in place. Peg heads are the workhorse component of commercial jewellery production and the foundation of the peg-and-claw setting construction. They are stocked by every major jewellery component supplier in standard sizes and styles, allowing setters to produce finished pieces in a fraction of the time required for full hand fabrication.

Construction and styles

Peg heads are produced by stamping, casting, or machining in karat gold, platinum, sterling silver, and palladium. Standard styles include the simple basket (an open cup with four or six claws), the crown or cathedral (a more elaborate skirted basket with decorative profile), the tiffany head (named for the classic six-prong solitaire used by Tiffany & Co. since 1886), the peg-set bezel, and various fancy-shape heads — oval, marquise, pear, cushion, emerald, princess. Sizes are graduated to match standard gem dimensions, with most suppliers offering increments of fractions of a millimetre across the typical range of stone sizes from melee to several-carat solitaires.

Soldering and installation

Installation involves drilling a hole in the mount sized to accept the peg, inserting the head with the peg through the hole, and soldering the joint with appropriate karat-matched solder. The soldering operation is brief but requires care: insufficient heat produces a cold joint that will fail in service, while excessive heat can damage adjacent components or distort the head itself. Goldsmithing manuals describe sizing the drill to provide a snug interference fit so that capillary action draws solder cleanly through the joint.

After soldering and cleanup, the stone is set into the head using standard claw-setting technique. The head's pre-formed claw spacing is sized to the standard stone dimensions, simplifying the setter's job; minor adjustment with bench-level pliers can accommodate slight variations.

Sizing and fit considerations

Selecting the right peg head requires matching three dimensions: the head's culet seat diameter to the stone's pavilion, the basket girdle opening to the stone's girdle diameter, and the peg diameter to the planned drilled hole. Component suppliers list these dimensions in catalogue specifications, and most setters maintain reference tables matching common stone sizes to standard head sizes. For non-standard or recut stones the bench jeweller may modify a head by trimming claws, opening or compressing the basket, or shortening the peg, retaining the time advantage while accommodating the unusual geometry.

In the trade

Peg heads are documented in goldsmithing manuals — Untracht, Wicks, McCreight — and the technique is standard in commercial production worldwide. For the working jeweller, the peg head is part of basic stock-keeping; a well-equipped bench will hold a range of standard sizes in karat gold and platinum to match common stone dimensions. Custom and bespoke work occasionally substitutes fully hand-fabricated heads where the design demands it, but peg heads serve the vast majority of commercial production by volume.

Further reading

• GIA — Jewellery design and fabrication references
• GIA Gems & Gemology — setting and fabrication articles
• International Gem Society — setting techniques