Minerals of Egypt
Mineralogy at the beginning of the nineteenth century was in a confused state, with several competing systems for classifying and describing specimens. François-Michel de Rozière, a mining engineer and one of Napoleon’s contingent of naturalists who were assigned to study and catalog the natural history of Egypt, thus had a vexing problem. How should he describe his rocks and minerals, when there was no agreed upon terminology? His inspired solution was to make detailed illustrations his primary method of presentation. And Rozière had the good fortune to be working on one of the most technically advanced projects for printing illustrations that had ever been undertaken. The mineralogy section in the Description de l’Égypte contains 115 illustrations, in full color, of the principal rocks found in Egypt’s landscape, and in its monuments. The plates are a stunning achievement. These, and the memoirs that he wrote for the Description, were François-Michel de Rozière’s only formal scholarly contribution to science. As a legacy, it is quite enough.
The properties that are needed to recognize rocks are not only the color, but also the mixture of colors and the texture. Rozière made sure that these qualities were brought out by the illustrations that he supervised for the Description. Each plate was printed in color, and then touched up by hand so that each figure had the features that distinguished that particular specimen. Even if one is not a geologist or a mineralogist, it is possible to begin to appreciate the qualities of the stone that the Egyptians used for their monuments. One can also appreciate the difficulty in distinguishing between different types of rocks. The Rosetta Stone, for example, was long described as a slab of basalt, but it is now recognized as being a piece of black granite.
Syenite is abundant in Egypt, particularly in the ancient quarries near the city of Syene, or Aswan, at the southern limit of ancient Egypt. For Rozière’s very first illustration, he chose, appropriately, the most common ornamental stone of Syene, which he called Oriental red granite. It is the stone that was used by the ancient Egyptians for many of the colossal statues, and for all the obelisks at Thebes, Alexandria, and Heliopolis, and for those that had been transported to Rome. This is the stone, Rozière pointed out, that Pliny mentioned in the second century, naming it syenite in his encyclopedic Natural History.
The magnificent plates of the rocks of Egypt, prepared under the close supervision of Rozière, were more than just illustrations. They were a means of visually expressing information in an accurate and detailed manner. When combined with his textual explanations of the plates, Rozière’s contribution to the geology and mineralogy of Egypt became a significant work of reference.
The other significant contribution by Rozière was a very long study of the physical geography of Egypt. It was substantial enough to be a separate book, but it was published as part of the textual memoirs of the Description de l’Égypte. There he astutely observed that every aspect of Egyptian culture, its religion, laws, and customs, was dependent on a single physical feature — the rise and fall of the Nile. That made Egypt unique among civilized nations.