corundum, inclusions.5, gems

An important early study by David Brewster of liquid inclusions enclosed within minerals. Brewster describes cavities containing two immiscible fluids with markedly different physical properties and examines their behavior under changes of temperature and pressure. Using microscopic observation and optical methods, he investigated the relative volumes, expansion and contraction of the enclosed fluids and the formation and movement of bubbles within the cavities. The paper is a major early contribution to the study of fluid inclusions and is especially important to gemology and mineralogy because such inclusions later became valuable evidence for mineral growth conditions, geological environment and, in some cases, geographic origin.