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Over half of the lead produced in the world comes from just four regions and nations: the United States, Russia, other members of the former Soviet Union, Australia, and Canada. In the United States, about 90% of all lead comes from seven mines in Missouri, with the rest originating from mines in Colorado, Idaho, and Utah.
- Lead
Lead is one of the first elements known to human societies....
- Lead
Since lead is easily extracted from its ores, prehistoric people in the Near East were aware of it. Galena is a principal ore of lead which often bears silver. Interest in silver helped initiate widespread extraction and use of lead in ancient Rome.
Lead has been mined for more than 6,000 years, and the metal and its compounds have been used throughout history. Small lead nuggets have been found in pre-Columbian Peru, Yucatan, and Guatemala.
Lead is one of the first elements known to human societies. It is described in some of the oldest books of the Old Testament and was widely used by some early civilizations. Examples of objects containing lead from fifth millennium Egyptian cultures have been found.
Lead has been known since ancient times. It is sometimes found free in nature, but is usually obtained from the ores galena (PbS), anglesite (PbSO 4), cerussite (PbCO 3) and minum (Pb 3 O 4). Although lead makes up only about 0.0013% of the earth's crust, it is not considered to be a rare element since it is easily mined and refined.
23 Σεπ 2013 · Lead is found in nature, rarely in pure form but in ores with other metals — the most abundant one in the Earth's crust being galena (PbS). Natural formation of lead occurs by radioactive...
Lead production dates back at least 8,000 years. Lead was used in Egypt as early as 5,000 B.C. , and in the time of the Pharaohs it was used in pottery glazes and as solder. It was also cast into ornamental objects. A white lead paint was also used in ancient Egypt, Greece, and Rome.
