Gem and Diamond Workers — Tasks

Task statements

• Assign polish, symmetry, and clarity grades to stones, according to established grading systems.
• Identify and document stones' clarity characteristics, using plot diagrams.
• Estimate wholesale and retail value of gems, following pricing guides, market fluctuations, and other relevant economic factors.
• Examine gems during processing to ensure accuracy of angles and positions of cuts or bores, using magnifying glasses, loupes, or shadowgraphs.
• 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.
• Examine gem surfaces and internal structures, using polariscopes, refractometers, microscopes, and other optical instruments, to differentiate between stones, to identify rare specimens, or to detect flaws, defects, or peculiarities affecting gem values.
• Advise customers and others on the best use of gems to create attractive jewelry items.
• Locate and mark drilling or cutting positions on stones or dies, using diamond chips and power hand tools.
• Secure gems or diamonds in holders, chucks, dops, lapidary sticks, or blocks for cutting, polishing, grinding, drilling, or shaping.
• Select shaping wheels for tasks, and mix and apply abrasives, bort, or polishing compounds.
• Measure sizes of stones' bore holes and cuts to ensure adherence to specifications, using precision measuring instruments.
• Sort rough diamonds into categories based on shape, size, color, and quality.
• 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.
• Hold stones, gems, dies, or styluses against rotating plates, wheels, saws, or slitters to cut, shape, slit, grind, or polish them.
• Replace, true, and sharpen blades, drills, and plates.
• Secure stones in metal mountings, using solder.
• Immerse stones in prescribed chemical solutions to determine specific gravities and key properties of gemstones or substitutes.
• Regrind drill points, and advance drill cutting points according to specifications for channel depths and shapes.
• Split gems along pre-marked lines to remove imperfections, using blades and jewelers' hammers.
• Lap girdles on rough diamonds, using diamond girdling lathes.
• Dismantle lapping, boring, cutting, polishing, and shaping equipment and machinery to clean and lubricate it.
• Regulate the speed of revolutions and reciprocating actions of drilling mechanisms.