Although jadeite is one of the more common gem materials to be imitated, seldom is the imitation mounted in an ornate setting made with quality craftsmanship. The East Coast lab recently received just such a piece in the form of a pendant.

The fully backed white metal pendant was stamped “18K.” It included numerous channel-set transparent near-colorless baguettes, as well as some transparent near-colorless marquise brilliants, all bordered by millgrain detailing. The pendant showcased a large, thin, semi-transparent to translucent green tablet—carved with the image of a stork—which measured approximately 33.40 × 40.25 × 1.65 mm (see figure).

The carved material showed an uneven “patchy” green color throughout, which to the untrained observer might have appeared similar to the aggregate structure of jadeite. We obtained a spot refractive index of 1.60 using a standard gemological refractometer. Patches of the tablet fluoresced a medium chalky yellow to long-wave UV radiation and a very weak chalky yellow to short-wave UV. Using a standard gemological microscope (50×) and fiber-optic lighting, we observed patches of tiny gas bubbles. Higher magnification (200×) revealed a fern-like structure that is commonly seen in the manufactured glass known in the trade as "Meta-jade.” The partially devitrified structure confirmed that the carving was a manufactured glass.