Old Market House (Galena, Illinois) Old Market House (Galena, Illinois) The Old Market House, currently being operated as the Galena Welcome Center, is a brick building built in the Greek Revival style in 1845 in Galena, Illinois. It is owned and operated by the Illinois Historic Preservation Agency as an Illinois State Historic Site. The Old Market House was built by the city of Galena to serve as a city hall and enclosed public farmer's market. A rapid increase in population in the Galena area in the 1830s and 1840s, largely a result of the discovery of galena, a kind of lead ore found in
Primary minerals Primary minerals A primary mineral is any mineral formed during the original crystallization of the host igneous primary rock and includes the essential mineral(s) used to classify the rock along with any accessory minerals. In ore deposit geology, hypogene processes occur deep below the earth's surface, and tend to form deposits of primary minerals, as opposed to supergene processes that occur at or near the surface, and tend to form secondary minerals. The elemental and mineralogical composition of primary rocks is determined by the chemical composition of the volcanic or magmatic flow from which it is formed. Extrusive rocks (such