Small “Surprise” in Elbaite Tourmaline
The “exclamation point” inclusions were identified as diopside crystals using Raman spectroscopy. Photomicrograph by Shu-Hong Lin; field of view 4.11 mm.
Recently, a 0.86 ct orange-yellow elbaite tourmaline cabochon was submitted to Taiwan Union Lab of Gem Research (TULAB) for identification service. The stone contained many prismatic and round xenocrysts. Among these inclusions was a prismatic crystal associated with a round crystal, a composition resembling an exclamation point (see above). The crystals were later confirmed to be diopside using Raman spectroscopy. Darkfield illumination, plane polarized light, and extended depth of field were adopted to obtain a clear microscopic image of this little “surprise” inside the gemstone.
