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Copper is used largely in the arts and manufactures as 
wire, sheet copper, and in the production of alloys, and for num- 
erous other purposes. 
Case 6 . — Represent the ores and rocks of a copper mine, 
Bisbee, Arizona. 
Cases B, C, and D. — Metallurgy of copper and the appli- 
cations of the metal. 
ZINC. 
Cases E, F, 6, 7, 8, 9, and lO. — Zinc ores. 
Sphalerite, or blende, is the most common of all the zinc 
minerals, containing 67 per cent, of zinc. It occurs massive and 
Handsomely crystallized in a variety of colors. The crystals have 
a resinous lustre and easy cleavage. Other zinc ores shown are: 
Smithsonite (carbonate of zinc); Calamine (silicate of zinc), or 
a combination of these minerals. 
Zinc does not occur in the metallic state in nature. It is found 
chemically combined with one or more elements in the different 
zinc minerals. 
The lead regions of Illinois, Missouri, and Kansas are heavy 
producers of zinc ore. Zinc is used extensively in the arts and 
manufactures ; as sheet zinc for galvanic batteries and coating 
wire, in the production of alloys, zinc paint, and for other pur- 
poses. 
TIN. 
Cases 11, 12, and 13 . — Tin ores, — Cassiterite and 
Stream Tin. 
The only ore that seems to be relied upon as a source of tin 
is cassiterite, an oxide which contains about 78 per cent. When 
found in placer deposits it is called stream tin. It is found in 
