A Red Herring in a Red Garnet
At first glance, a 2.54 ct round mixed-cut stone examined by the author presented itself as a natural red garnet. Microscopic inspection revealed a host of transparent crystals and widespread epitaxial needles, both typical inclusions for garnet. Upon closer inspection, however, some of the apparent “crystals” were recognized as gas bubbles, betrayed by their smooth spherical forms (see above). This distinction can be easily missed without careful examination under high magnification. Additional observations and testing conclusively identified the material as pyrope-almandine garnet fused with manufactured glass. As with most garnet-topped doublets, the garnet portion was cut to occupy the crown while the glass made up most of the pavilion so that the natural inclusions of the garnet top masked the telltale signs of manufactured glass beneath.
