gems, history of gemology, history of mineralogy, Arabic mineralogy, history of science, crystallography

Recent scholarship has greatly extended our understanding of the history of theories concerning the ultimate nature and structure of matter. This is particularly true for the period preceding the emergence of Dalton’s atomic theory. We now know something of the hierarchical theories of material structure prevalent in the seventeenth century, in the thought of Robert Boyle and Isaac Newton, for example. We have begun to perceive how important Newton’s ideas concerning the structure of matter and the forces that bound substances together or pulled them apart were for the physical and chemical philosophers of the eighteenth century. Dalton’s chemical atomic theory no longer appears quite so lacking in background as it did twenty-five years ago. At the same time, Dalton’s true innovation in turning from consideration of force to consideration of atomic weight has likewise been clarified.