gems, history of gemology, Pliny, Arabic mineralogy

Of Pliny’s works, only one has come down to us—his Natural history. It is not, strictly speaking, what in our modern language we would understand by a similar title. The author begins by presenting ideas about the world, the earth, the sun, the planets, and the remarkable properties of the elements. From there, he moves on to the geographical description of the parts of the earth known to the ancients. After geography comes what we would call natural history—namely, the history of land animals, fish, insects, and birds. The botanical section that follows is quite substantial, all the more so because Pliny includes a great deal of information about the arts, such as the making of wine and oil, the cultivation of grains, and various industrial applications. Once the botanical part is finished, he returns to animals in order to list the remedies they provide; finally, he moves on to mineral substances, and there (in what is one of the most interesting parts of his book) he recounts both the history of the extraction processes for these substances and the history of painting and sculpture among the ancients. One can see that, in truth, Pliny’s work is a kind of encyclopedia.