The mineral treasures of the Empire were various and abundant. It has been noticed already that Persia Proper, if we include in it Carmania, possessed mines of gold, silver, copper, iron, red lead, orpiment, and salt, yielding also bitumen, naphtha, sulphur, and most probably common lead. We are further informed by ancient writers that Drangiana, or Sarangia, furnished the rare and valuable mineral tin, without which copper could not be hardened into bronze; that Armenia yielded emery, so necessary for the working and polishing of gems; that the mountains and mines of the Empire supplied almost all the varieties of useful and precious stones; and that thus there was scarcely a mineral known to and required by the ancients for the purposes of their life which the Great King could not command without having recourse to others than his own subjects. It may be likewise noticed that the more important were very abundant, being found in many places and in large quantities. Gold was furnished from the mountains and deserts of Thibet and India, from the rivers of Lydia, and probably from other places where it is still found, as Armenia, Cabul, and the neighborhood of Meshed. Silver, which was the general medium of exchange in Persia, must have been especially plentiful. It was probably yielded, not only by the Kerman mines, but also by those of Armenia, Asia Minor, and the Elburz. Copper was obtained in great abundance from Cyprus, as well as from Carmania; and it may have been also derived, as it is now in very large quantities, from Armenia. Iron, really the most precious of all metals, existed within the Persian territory in the shape of huge boulders, as well as in nodules and in the form of ironstone. Lead was procurable from Bactria, Armenia, Korman, and many parts of Affghanistan; orpiment from Bactria, Kerman, and the Hazareh country; antimony from Armenia, Affghanistan, and Media; hornblende, quartz, talc, and asbestos, from various places in the Taurus. Of all necessary minerals probably none was so plentiful and so widely diffused as salt. It was not only in Persia Proper that nature had bestowed this commodity with a lavish hand--there was scarcely a province of the Empire which did not possess it in superfluous abundance. Large tracts were covered by it in North Africa, in Media, in Carmania, and in Lower Babylonia. In Asia Minor, Armenia, Syria, Palestine, and other places, it could be obtained from lakes. In Kerman, and again in Palestine, it showed itself in the shape of large masses, not inappropriately termed “mountains.” Finally, in India it was the chief material of a long mountain-range, which is capable of supplying the whole world with salt for many ages.