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
Mineral processing is not completely known and further research into their mechanisms is being performed. Depressants and activators are used to selectively separate one mineral from another. Depressants inhibit the flotation of one mineral or minerals while activators enable the flotation of others. Examples of these include CN, used to depress all sulfides but galena and this depressant is believed to operate by changing the solubility of chemisorbed and physisorbed collectors on sulfides. This theory originates from Russia. An example of an activator is Cu ions, used for the flotation of sphalerite. There are a number of cells able to be used