Galena Sardinia. In the United States, it occurs most notably in the Mississippi Valley type deposits of the Lead Belt in southeastern Missouri, and in the Driftless Area of Illinois, Iowa and Wisconsin. Galena also was a major mineral of the zinc-lead mines of the tri-state district around Joplin in southwestern Missouri and the adjoining areas of Kansas and Oklahoma. Galena is also an important ore mineral in the silver mining regions of Colorado, Idaho, Utah and Montana. Of the latter, the Coeur d'Alene district of northern Idaho was most prominent. Galena is the official state mineral of the U.S. states
Mineral resource classification Mineral resource classification Mineral resource classification is the classification of mineral resources based on an increasing level of geological knowledge and confidence. Mineral deposits can be classified as: In common mining terminology , an "ore deposit" by definition must have an 'ore reserve', and may or may not have additional 'resources'. Classification, because it is an economic function, is governed by statutes, regulations and industry best practice norms. There are several classification schemes worldwide, however the Canadian CIM classification (see NI 43-101), the Australian Joint Ore Reserves Committee Code (JORC Code), the South African Code for the Reporting of Mineral