Gems in Hellenistic and Roman Jewellery of Northern Greece: An investigation from the Collections of the Archaeological Museum of Thessaloniki, Greece

Emerald is the green variety of beryl, with its distinctive color resulting from trace amounts of ch

Yuri Shelementyev, Galina Kriulina, Olga Yarapova, Viktor Vins, and Alexander Stolyarevich

Most of the spinels are found in shades of red to purple. Colourless, green and cobalt bearing varie