A dop stick — commonly shortened to dop — is a cylindrical rod used to hold a rough or partially worked gemstone securely during faceting, cabochon cutting, or polishing. Typically machined from brass or aluminium, though wooden versions remain in use for certain traditional applications, the dop stick presents a flat or pre-formed end against which the stone is bonded with an adhesive, most often heated dop wax or a two-part epoxy. The opposite end is sized to fit the collet chuck of a faceting machine or the spindle of a cabbing unit, making the dop stick the critical mechanical interface between the stone and the cutting instrument.

Construction and Materials

Commercial dop sticks are manufactured in a standardised range of diameters — commonly from approximately 4 mm up to 25 mm or more — so that the working face of the dop closely matches the girdle diameter of the stone being cut. A well-matched dop minimises rocking and lateral movement, which would otherwise introduce error into facet angles or produce an uneven cabochon profile. Brass is the most widely favoured material because it machines cleanly, holds wax adhesion reliably, and resists the minor corrosion introduced by water-based coolants. Aluminium dops are lighter and conduct heat more slowly, a property sometimes preferred when working heat-sensitive stones such as opal or certain treated corundum. Wooden dops, turned from hardwood dowel, are occasionally used for very large or irregularly shaped rough where a custom-shaped wax seat is built up freehand.

Pre-formed or V-dop variants feature a shallow conical recess at the working end, which cradles a round or oval girdle and centres the stone automatically before the wax sets. Flat-faced dops are used for stones that will be oriented with a flat table or a flat base resting against the adhesive bed.

Attachment Methods

The traditional attachment medium is dop wax, a shellac-based thermoplastic compound that softens at temperatures between roughly 65 °C and 80 °C. The cutter heats the dop stick over an alcohol lamp or purpose-built dop heater, applies a bead of wax to the face, warms the stone gently to prevent thermal shock, and seats the stone into the wax, aligning the desired cutting axis before the wax hardens. The bond is strong enough to resist the lateral forces of grinding and polishing yet releases cleanly when reheated, leaving minimal residue.

Two-part epoxy adhesives are increasingly used, particularly in production cutting environments, because they cure at room temperature and produce a rigid, vibration-resistant bond. The trade-off is a longer cure time and the need for a solvent — typically acetone — to release the stone cleanly. Some cutters use cyanoacrylate adhesive for very small stones or for transfer operations where a thin, precise bond is required.

The Transfer Operation

Because a faceted stone requires work on both its crown and its pavilion, the cutter must reverse the stone at the midpoint of the cutting sequence. This procedure — known as transfer dopping or simply the transfer — involves bonding a second dop to the completed half of the stone while it is still mounted on the first, so that the two dops are held in precise axial alignment in a transfer block or transfer jig. Once the adhesive on the second dop has set, the first dop is released by heat or solvent. The accuracy of the transfer directly determines whether the finished stone's crown and pavilion meet cleanly at the girdle, making it one of the most consequential steps in the faceting process.

In the Trade

Dop sticks are consumable workshop items, sold individually or in sets by lapidary suppliers worldwide. A working faceter typically maintains a range of sizes and may accumulate dozens of dops dedicated to recurring stone shapes or sizes. The condition of the working face — free of old wax residue, undamaged, and truly flat or correctly profiled — is considered a basic prerequisite of accurate work. Worn or bent dops are routinely replaced rather than reconditioned. Despite the simplicity of the object, experienced cutters are particular about dop quality, since any eccentricity or looseness in the chuck fit propagates directly into the geometry of the finished gem.