Mineralogy, the science of minerals. Mineralogists identify and classify minerals by chemical composition and physical properties. They also study the natural processes that form and change minerals. Mineralogy is closely related to petrology, the study of rocks; and to crystallography, the study of crystals.

Mineralogy has practical applications in mining and metallurgy; in soil analysis for agriculture and forestry; in various branches of engineering; and in pharmacy, which uses many mineral remedies. Mineralogists have made important theoretical contributions to geology, chemistry, and physics. Mineral collecting is a popular hobby.

Mineralogy began in the mid-16th century with the studies of the German scientist Georgius Agricola, who is regarded as the father of mineralogy. He determined the origin of certain minerals and rocks and also wrote what is considered the first mineralogy textbook. Mineralogy became a separate science in the late 18th century largely through the works of the German geologist Abraham Werner. In 1837 James D. Dana, an American mineralogist, published System of Mineralogy, which provided the basis for modern mineral classification.