Supplemental

• Examine diamonds or gems to ascertain the shape, cut, and width of cut stones, or to select the cuts that will result in the biggest, best quality stones.
• Immerse stones in prescribed chemical solutions to determine specific gravities and key properties of gemstones or substitutes.
• Hold stones, gems, dies, or styluses against rotating plates, wheels, saws, or slitters to cut, shape, slit, grind, or polish them.
• Sort rough diamonds into categories based on shape, size, color, and quality.
• Secure gems or diamonds in holders, chucks, dops, lapidary sticks, or blocks for cutting, polishing, grinding, drilling, or shaping.
• Locate and mark drilling or cutting positions on stones or dies, using diamond chips and power hand tools.
• Place stones in clamps on polishing machines and polish facets of stones, using felt-covered or canvas-covered polishing wheels and polishing compounds such as tripoli and rouge.
• Lap girdles on rough diamonds, using diamond girdling lathes.
• Measure sizes of stones' bore holes and cuts to ensure adherence to specifications, using precision measuring instruments.
• Select shaping wheels for tasks, and mix and apply abrasives, bort, or polishing compounds.
• Split gems along pre-marked lines to remove imperfections, using blades and jewelers' hammers.
• Regulate the speed of revolutions and reciprocating actions of drilling mechanisms.
• Replace, true, and sharpen blades, drills, and plates.
• Secure stones in metal mountings, using solder.
• Dismantle lapping, boring, cutting, polishing, and shaping equipment and machinery to clean and lubricate it.
• Regrind drill points, and advance drill cutting points according to specifications for channel depths and shapes.