The lozenge graver is a hand engraving tool whose working tip is ground in the form of a slender four-sided rhombus, presenting a sharp central point with two side cutting edges that meet at acute angles. It is part of the standard set of bench gravers used by jewellery engravers, stone setters, and hand-finishers, alongside the flat, round, knife, onglette, and bullsticker.

Geometry

The cross-section of a lozenge graver is a rhombus whose acute apex angle is ground typically between 90 and 120 degrees, depending on the depth of cut and the hardness of the metal being worked. Below the cutting edges the body of the tool is square or rectangular in section, set into a wooden mushroom handle with the spine seated against the heel of the palm. The face is sharpened at a heel angle of roughly 45 degrees, producing a single point capable of starting a cut anywhere on a flat or contoured surface.

Use in setting and engraving

In stone setting the lozenge graver is used to raise and shape beads, cut down bezel walls, and produce the bright cuts that border pave and grain settings. The narrow point allows the setter to work into tight corners between stones, while the side edges cut clean, V-section channels. In hand engraving the tool produces fine line work, decorative shading, and the cross-hatched grounds typical of script and monogram engraving. Modern pneumatic engraving systems such as the GRS GraverMach hold lozenge gravers in interchangeable handpieces, allowing controlled impact at high frequency.

Sharpening and material

Lozenge gravers are most often made from high-speed steel (HSS) or carbide, the latter favoured for repetitive production work in platinum and white gold. Sharpening is performed on diamond laps or fixtures such as the GRS Power Hone, which holds the established geometry to within a degree across multiple resharpens. The shape is unforgiving of chipping at the point, and a worn or rounded tip is rejected immediately by experienced setters.