Boyleite is a noun that refers to a rare mineral found in underground mines, specifically in the salt deposits of the Pekin Member in Illinois, United States. The mineral was named after Richard J. Boyle, a professor of chemistry at the University of Illinois, who extensively studied salt deposits. Boyleite is classified as a sulfate mineral and belongs to the barite group.
The physical properties of boyleite include a waxy or vitreous luster and a transparent to translucent appearance. It typically occurs as small, prismatic crystals that can range in color from colorless to pale yellow or green. The crystals often exhibit a characteristic tabular or platy shape.
Chemically, boyleite consists of hydrous calcium, magnesium, and sulfate ions. Its chemical formula is Ca(Mg,Zn)(SO4)·4H2O. It is closely related to other minerals within the barite group, such as barite itself (BaSO4) and zincobotryogen (ZnSb2O6·6H2O).
Boyleite is primarily formed through the alteration of other minerals in the presence of sulfides and oxygen. It is typically found along with minerals like halite, gypsum, sylvite, and anhydrite.
Due to its scarcity and limited occurrence, boyleite does not have significant industrial applications. However, it is valued by mineral collectors for its unique crystal morphology and attractive color variations. Its identification requires specialized laboratory techniques, such as X-ray diffraction and electron microscopy, due to its similarity to other minerals within the barite group.
