Facetron
Facetron
A benchmark American faceting machine by Jarvi Tool Company
The Facetron is an American faceting machine manufactured by Jarvi Tool Company, designed for cutting and polishing faceted gemstones on a horizontal rotating lap. Introduced in the mid-twentieth century, it became one of the most widely adopted machines among both hobbyist and professional faceters in North America, and its robust construction has ensured a lasting presence on the second-hand market long after production of certain models ceased.
Design and Mechanics
The Facetron employs a mast-and-quill architecture standard to precision faceting machines. The mast is a vertical post along which the quill — the arm holding the gemstone dop — travels up and down to control cutting depth. Angle settings are read from a protractor-style scale mounted on the mast, allowing the operator to set the precise pavilion or crown angle required by a given faceting diagram. The index gear, which controls the rotational position of the stone around its vertical axis, is gear-driven rather than friction-based, providing repeatable, click-stop positioning at standard index divisions.
The horizontal lap spins on a motorised spindle beneath the quill. Laps of varying grit — from coarse metal-bonded diamond laps for rough shaping through to fine ceramic or oxide polishing laps — are interchangeable on the same spindle, a feature common to most precision faceting machines of this class.
Construction and Reputation
The Facetron earned a reputation for mechanical solidity. Its cast and machined metal components gave it greater rigidity than lighter or partially plastic competitors, which translated into consistent angle repeatability — a critical quality when cutting matched sets or reproducing a design across multiple stones. The protractor scale, while analogue rather than digital, was considered sufficiently precise for the vast majority of amateur and commercial cutting work. United States Faceters Guild literature has documented the Facetron as a reference machine in instructional contexts, and it appears frequently in lapidary equipment histories as representative of mid-century American precision tool manufacturing.
Place in the Faceting Community
The Facetron occupies a position in the faceting world broadly analogous to that of a well-regarded vintage scientific instrument: no longer at the frontier of design innovation, yet trusted, well-understood, and supported by an established community of users. Replacement parts, compatible laps, and instructional resources specific to the machine remain accessible. For a beginning faceter, a used Facetron in good condition is frequently recommended as a reliable entry point; for an experienced cutter, its predictability makes it suitable for production work on standard designs.
More recent machine designs — including digital-angle models and those with finer index divisions — have expanded the options available to faceters, but the Facetron's longevity in the market reflects the enduring value of straightforward mechanical precision over electronic complexity for many practitioners.