Diamond Pacific is an American manufacturer of lapidary machinery, founded in California in the mid-twentieth century and best known for producing the Genie and Pixie series of cabochon-grinding machines. The company's equipment has become a benchmark in North American hobby and small-scale professional lapidary work, offering integrated multi-wheel systems that carry a rough stone through successive stages of grinding, sanding, and polishing in a single compact unit.

Design and Construction

Diamond Pacific cabbing machines are built around a horizontal arbour that drives a series of expandable rubber wheels, each charged with a different abrasive medium. A typical Genie configuration presents six wheels in sequence: coarse diamond-impregnated wheels for initial shaping, progressively finer diamond or silicon-carbide wheels for refining the dome profile, and felt or leather polishing wheels for the final buff. Water is delivered continuously to each wheel through a drip or spray system, cooling the stone, extending wheel life, and controlling the fine slurry that would otherwise become airborne. Adjustable speed controls allow the operator to match wheel surface velocity to the hardness and sensitivity of the material being worked.

The Pixie is a smaller, lighter variant intended for bench-top use in confined workshops or for lapidaries who work primarily with smaller calibrated stones. Larger production-oriented models in the Diamond Pacific range accommodate wider wheels and higher throughput, though the underlying engineering philosophy — sequential abrasive grades on a single driven shaft with integrated water cooling — remains consistent across the line.

Abrasive Systems

Diamond Pacific machines are compatible with both bonded-diamond and silicon-carbide abrasive wheels, though the company's own diamond-charged expandable drums have largely displaced silicon-carbide belts in contemporary workshop practice owing to their longer service life and more consistent cutting action. Grit progressions typically run from 80 or 100 mesh for rough shaping through 220, 400, 600, and 1200 mesh, finishing on a polishing compound such as cerium oxide, aluminium oxide, or tin oxide applied to a soft wheel. The choice of final polish compound depends on the mineral being worked: cerium oxide suits many silicates, while harder materials such as corundum or chrysoberyl may require a diamond paste at the polishing stage.

Place in the Lapidary Trade

Diamond Pacific equipment has been reviewed and discussed extensively in Lapidary Journal Jewelry Artist, the principal North American periodical for the amateur and semi-professional gem-cutting community, and the machines are a familiar fixture at gem and mineral shows throughout the United States and Canada. Their reputation rests on mechanical reliability, the ready availability of replacement wheels and parts, and a design that allows a relative beginner to produce presentable cabochons within a short learning period. For these reasons they are frequently recommended as a first machine by lapidary instructors and club programmes.

Professional gem cutters working at commercial scale may graduate to larger, more specialised grinding equipment, but Diamond Pacific cabbers retain a presence even in professional settings where versatility and compact footprint are valued. The machines are particularly well suited to working translucent and opaque materials — agates, jaspers, chrysoprase, turquoise, labradorite, and similar stones — that constitute the bulk of cabochon production in the North American market.

Further Reading

• Gems & Gemology — GIA
• American Gem Trade Association (AGTA)