Assign polish, symmetry, and clarity grades to stones, according to established grading systems.
Estimate wholesale and retail value of gems, following pricing guides, market fluctuations, and other relevant economic factors.
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.
Identify and document stones' clarity characteristics, using plot diagrams.
Advise customers and others on the best use of gems to create attractive jewelry items.