A recently examined 1.17 ct green stone exhibited dense tube inclusions running parallel to the c-axis (see above). The stone was identified as a Colombian emerald based on trace element chemistry measured by laser ablation–inductively coupled plasma–mass spectrometry analysis (S. Saeseaw et al., “Geographic origin determination of emerald,” Winter 2019 G&G, pp. 614–646), and the profile was similar to that of samples from the Chivor district.
Long growth tubes are common inclusions in colored beryl-group gemstones that form in fluid-rich environments (e.g., Winter 2023 G&G Micro-World, p. 503; Fall 2024 Lab Notes, pp. 379–380). In this stone, the linear pavilion facet edges created the illusion of a corridor through a tranquil bamboo forest. The sawtooth graining occasionally observed in Colombian emeralds also was present, reminiscent of sunlight filtering through the bamboo. These impressions were enhanced as the emerald was imbued with a refreshing green color resulting from trace amounts of chromium and vanadium.
Taku Okada is a staff gemologist at GIA in Tokyo.
A recently examined 1.17 ct green stone exhibited dense tube inclusions running parallel to the c-axis (see above). The stone was identified as a Colombian emerald based on trace element chemistry measured by laser ablation–inductively coupled plasma–mass spectrometry analysis (S. Saeseaw et al., “Geographic origin determination of emerald,” Winter 2019 G&G, pp. 614–646), and the profile was similar to that of samples from the Chivor district.
Long growth tubes are common inclusions in colored beryl-group gemstones that form in fluid-rich environments (e.g., Winter 2023 G&G Micro-World, p. 503; Fall 2024 Lab Notes, pp. 379–380). In this stone, the linear pavilion facet edges created the illusion of a corridor through a tranquil bamboo forest. The sawtooth graining occasionally observed in Colombian emeralds also was present, reminiscent of sunlight filtering through the bamboo. These impressions were enhanced as the emerald was imbued with a refreshing green color resulting from trace amounts of chromium and vanadium.
Taku Okada is a staff gemologist at GIA in Tokyo.
