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Esimerkit

• You can easily extract lead from galena, a natural mineral which has been used in crystal radio receivers.
• The galena of the ore contains microscopic inclusions of various forms that become visible upon polished surfaces etched with hydrochloric or nitric acid.
• These samples had higher Pb206 and Pb208 abundances than any other galenas yet examined.
• Very little galena has been reported (recovered mostly from burial mounds) in the Great Lakes region indicating that the mineral was not a major interregional exchange commodity during this period. However, numerous galenas have been recovered from the lower Mississippi Valley region and Florida indicating that galena was part of an important north-south exchange system (Walthall 1981).