NATIVE LEAD

Chemistry: Pb, Elemental Lead
CLASS: Elements
GROUP: Gold
Uses: Only as mineral specimens. However, processed lead has many uses.
Specimens

Lead is extremely rare as a mineral, though the element itself somewhat common. The element lead is found in the Earth's crust in concentration of about 13 parts per billion. Not exactly the most common element, however as a very important metal it is fortunate that lead often concentrates itself in ore bodies of galena, cerussite, anglesite and minium.

The element lead does not lend itself well to form crystals of its own and thus the mineral lead is only rarely seen. It has been found with gold in placer deposits and in unusual metamorphosed limestones and marbles. It is far too rare to be a serious ore of lead.

Lead has an almost white color and is very soft, capable of being scratched by a fingernail. With its metallic luster and high density the mineral lead can not be easily confused for any other mineral.

Lead ore was found in Colorado as a result of an early gold rush. The lead ore contained a significant percentage of silver, and was mined for that purpose and led to the founding of the mining town, Leadville. In addition to producing 240,000 ounces of silver, the mines produced nearly a billion tons of lead and more than a half-billion tons of zinc.

PHYSICAL CHARACTERISTICS:

Color is a whitish gray.
Luster is metallic.
Transparency is opaque.
Crystal System is isometric; 4/m bar 3 2/m
Crystal Habits include small flat platelets and small grains
Cleavage is absent.
Fracture is jagged.
Streak is gray.
Hardness is 1.5
Specific Gravity is 11.3+ (very heavy even for metallic minerals)
Associated Minerals include gold, calcite and hematite.
Other Characteristics: ductile, malleable and sectile, meaning it can be pounded into other shapes, stretched into a wire and cut into slices.
Notable Occurrences includes Franklin, New jersey, USA; Harstig Mine, Sweden; Vera Cruz, Mexico and in placer mines especially in the Ural Mountains of Russia. In the past, the Leadville Mining District in Colorado, USA was a major producer of lead - nearly a billion tons.
Best Field Indicators are color, density, hardness, luster and ductility.