corundum, quality.10, Afghanistan.12, Tajikistan.12, gems

Barbaro recounts his fifteenth-century travels to Tana on the Sea of Azov and through Persia, describing the countries, peoples, rulers, customs, commerce, routes, and natural products encountered during his journeys. His observations provide firsthand information on regions linking the Black Sea, Caucasus, Persia, and Central Asia during a period of extensive Venetian commercial activity. Of particular gemological interest are pp. 53–60, where he describes precious stones and their reputed sources, including the celebrated balas rubies associated with Badakhshan and other valuable materials entering Persian and international trade. The account is an important early European source for knowledge of the gemstone-producing regions and trading networks of Persia and Central Asia.