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
Nickeline parts per million. However, arsenic bearing nickel ore may be treated by blending with 'clean' ore sources, to produce a blended feedstock which the mill and smelter can handle with acceptable recovery. The primary problem for treating nickeline in conventionally constructed nickel mills is the specific gravity of nickeline versus that of pentlandite. This renders the ore difficult to treat via the froth flotation technique. Within the smelter itself, the nickeline contributes to high arsenic contents which require additional reagents and fluxes to strip from the nickel metal. Nickeline Nickeline or niccolite is a mineral consisting of nickel arsenide (NiAs)