Goods arrive sealed and anonymised. They are examined by instrument and by eye, by graders who do not know the client, and released only when independent opinions agree.
Loose polished diamonds from 0.15 ct upward, graded for colour, clarity, cut, polish, symmetry and fluorescence, with plotted inclusions and full proportion measurements. Every stone is screened for laboratory-grown origin and for treatment before grading begins.
Grown diamonds graded on the established scales, with growth method identified and any post-growth treatment recorded. The report is visually distinct from the natural diamond report and states the origin on the front, in full words.
Species and variety determination by refractometer, spectroscopy and microscopy, with treatment detection. Geographic origin is offered for ruby, sapphire and emerald where inclusion and trace evidence supports an opinion, and withheld where it does not.
Articles graded as they are worn. Metal and hallmarks verified, stones measured and estimated in the mount, ranges given rather than single grades because a mounted stone cannot be graded as a loose one.
Natural, cultured, or imitation, determined by radiography and microscopy. Nacre thickness, surface condition, processing and any dye or irradiation are recorded for single pearls and for strands.
A precise physical description, photographed and measured, for the appraiser or insurer who sets the figure. The institute supplies the facts and never the number, which is what keeps the facts worth having.
Trade clients submit at any laboratory counter or by insured courier with a completed take-in form. Private owners may submit through a member jeweler, or in person with proof of identity. Turnaround is quoted at take-in and held.
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