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The atomic number of lead is 82. That tells us that electrically neutral lead has 82 protons and 82 electrons. The three stable isotopes of lead are 206 Pb, 207 Pb, and 208â¦ Pb. These isotopes have 124, 125, and 126 neutrons per each atom, respectively.
It is bluish-white, very dense, and has a low melting point. Lead is found in veins and masses in limestone and dolomite. It is also found with deposits of other metals, such as zinc, silver, copper, and gold. Lead is essentially a co-product of zinc mining or a byproduct of copper and/or gold and silver mining. Complex ores are also the source of byproduct metals such as bismuth, antimony, silver, copper, and gold. The most common lead-ore mineral is galena, or lead sulfide (PbS). Another ore mineral in which lead is found combined with sulfur is anglesite or lead sulfate (PbSO 4).