The author recently examined a large 25.08 ct greenish blue beryl (aquamarine) containing numerous oriented small two-phase (liquid and gas) thin film inclusions. These inclusions were hardly visible in brightfield illumination but became reflective and iridescent when viewed with fiber-optic illumination (see above). The most diagnostic of beryl inclusions (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Volume 2, Opinio Publishers, Basel, Switzerland, 2005, pp. 312–314), the thin films were situated in planes perpendicular to the c-axis of the host. The thin films in this aquamarine resembled fireworks in the night sky.
Michaela Damba is a senior staff gemologist at GIA in Carlsbad, California.
The author recently examined a large 25.08 ct greenish blue beryl (aquamarine) containing numerous oriented small two-phase (liquid and gas) thin film inclusions. These inclusions were hardly visible in brightfield illumination but became reflective and iridescent when viewed with fiber-optic illumination (see above). The most diagnostic of beryl inclusions (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Volume 2, Opinio Publishers, Basel, Switzerland, 2005, pp. 312–314), the thin films were situated in planes perpendicular to the c-axis of the host. The thin films in this aquamarine resembled fireworks in the night sky.
Michaela Damba is a senior staff gemologist at GIA in Carlsbad, California.
