Recently, the authors observed a series of well-formed vivid green crystals in a colorless quartz specimen. Under a gemological microscope, these inclusions displayed high transparency, vitreous luster, and isometric morphology (see above). Confocal Raman spectroscopy confirmed the identity of the inclusions as grossular garnet. The green coloration designates its variety as tsavorite.
While quartz hosted by garnet is common, the reverse scenario is highly unusual. Grossular typically crystallizes during the early stages of contact metasomatism, whereas the host quartz usually precipitates from late-stage silica-saturated hydrothermal fluids. The grossular garnets in this specimen are presumed to have crystallized before the host quartz, representing a typical protogenetic inclusion. Overall, fully intact euhedral tsavorite crystals included in such a highly transparent quartz are exceedingly rare.
Liyan He is affiliated with Guangdong Gemstones & Precious Metals Testing Center in Guangzhou, China. Wang Zhang is affiliated with Min De Minerals & Gem Research Co., Ltd. in Nanjing, China.
Recently, the authors observed a series of well-formed vivid green crystals in a colorless quartz specimen. Under a gemological microscope, these inclusions displayed high transparency, vitreous luster, and isometric morphology (see above). Confocal Raman spectroscopy confirmed the identity of the inclusions as grossular garnet. The green coloration designates its variety as tsavorite.
While quartz hosted by garnet is common, the reverse scenario is highly unusual. Grossular typically crystallizes during the early stages of contact metasomatism, whereas the host quartz usually precipitates from late-stage silica-saturated hydrothermal fluids. The grossular garnets in this specimen are presumed to have crystallized before the host quartz, representing a typical protogenetic inclusion. Overall, fully intact euhedral tsavorite crystals included in such a highly transparent quartz are exceedingly rare.
Liyan He is affiliated with Guangdong Gemstones & Precious Metals Testing Center in Guangzhou, China. Wang Zhang is affiliated with Min De Minerals & Gem Research Co., Ltd. in Nanjing, China.
