Search

This article reports on the recent mining and production status of ruby in Longido, Tanzania. Faceted-grade rubies and their matrix from Longido Area, Tanzania, were investigated by standard gemological testing, including FTIR, UV-VIS, Raman spectra, and LA-ICP-MS. Microscopic observations revealed dense needle-like and triangular inclusions, distinct growth lines, and color banding as typical inclusions. In agreement with the Raman results, the transmission FTIR spectrum confirmed the presence of aluminum hydroxide. The Raman spectra identified associated minerals and inclusions, including zoisite, parasites, feldspar within the matrix, rutile, and diaspore in the ruby host. The chemistry analysis revealed a high amount of Cr and relatively low iron as a good indicator of geographic origin.

Gemstones usually contain inclusions as the natural hallmark of their formation. Studies on inclusions may contribute to our understanding of the gem and better adapt to the gems and jewelry industry. In this study, we applied advanced 3D Raman mapping and high-resolution X-ray computed tomography (HRXCT) and conducted a thorough experiment on one emerald with a special trapiche pattern containing a colorless core, solid minerals, and fluids. Hematite and magnetite were identified as metallic minerals by the Raman spectrum. The hexagonal core is beryl, and the voids are primarily filled with CO2 and N2. HRXCT demonstrated a visualized distribution of these inclusions within the gem host by reconstructing a 3D illustration. Further calculation of the volume of inclusions regarding the host showed that the minerals take up 0.07%, void 0.03%, and the hexagonal core 8.25%. The combined application of Raman-Mapping and X-ray Micro Computed Tomography proved to be a very promising technique for tracing the gemstones by characterizing the unique inclusions (identification and morphology) within the gem host.

When the same gems and precious metals are used in jewelry, design is the element that ultimately distinguishes one piece from another. Real success is measured not only by the value of its materials but also by the character and quality of the design and craftsmanship. Once considered a weak point of China's gem and jewelry industry, design has seen tremendous progress over the last decade. Benefiting from the availability of more gem materials and the power of a rapidly growing consumer market, Chinese designers now have the freedom to develop their design concepts and craftsmanship skills. Designers from mainland China, Hong Kong, and Taiwan share the bond of cultural identity and have found ways to create jewelry that expresses the Chinese soul. [ABSTRACT FROM AUTHOR]