Gemological study of faceted jewelry minerals from the Museum of Mineralogy, Petrography, and Resources at the University of Mining and Geology “St. Ivan Rilski” Sofia

Selected samples from the main gemological exposition in the Museum of Mineralogy, Petrography, and Resources at the University of Mining and Geology “St. Iv. Rilski” were analyzed using standard gemological equipment such as a refractometer, polariscope with conoscopic lens, diffraction grating spectroscope, dichroscope, Hanneman gem filter set, and 10x triplet magnification loupe. This study aimed to identify and characterize mineral varieties for their gemological quality and processing. The identified mineral varieties include almandines, almandine-spessartine, aquamarines, rubellites, spinel-red, blue sapphires, olivines, and seventy-three corundums of different colors and sizes. These results aid in classifying the studied samples and contribute to the existing database for each of them.