Galena, Illinois time. The city emerged as the largest steamboat hub on the Mississippi River north of St. Louis, Missouri. Galena was the home of Ulysses S. Grant and eight other Civil War generals. Today, the city is a tourist destination known for its history, architecture, and resorts. The city is named for galena, the natural form of lead sulfide (PbS) and the most important lead ore. Native Americans mined the ore for use in burial rituals. The Havana Hopewell first traded galena in the area during the Middle Woodland period (c. 1–400 CE). However, the use of galena in the Havana
Galena applied to pottery. Galena is a semiconductor with a small band gap of about 0.4 eV, which found use in early wireless communication systems. It was used as the crystal in crystal radio receivers, in which it was used as a point-contact diode capable of rectifying alternating current to detect the radio signals. The galena crystal was used with a sharp wire, known as a "cat's whisker" in contact with it. The operation of the radio required that the point of contact on the galena be shifted about to find a part of the crystal that acted as a rectifying