Pyromorphite is a
mineralA mineral is a naturally occurring solid formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure, and specific physical properties. A rock, by comparison, is an aggregate of minerals and/or mineraloids, and need not have a specific...
species composed of
leadLead is a main-group element with symbol Pb and atomic number 82. Lead is a soft, malleable poor metal, also considered to be one of the heavy metals. Lead has a bluish-white color when freshly cut, but tarnishes to a dull grayish color when exposed to air...
chlorophosphate:
PbLead is a main-group element with symbol Pb and atomic number 82. Lead is a soft, malleable poor metal, also considered to be one of the heavy metals. Lead has a bluish-white color when freshly cut, but tarnishes to a dull grayish color when exposed to air...
5(
PPhosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus is commonly found in inorganic phosphate rocks. Elemental phosphorus exists in two major forms - white phosphorus and red phosphorus...
OOxygen Oxygen Oxygen (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter) is the element with atomic number 8 and represented by the symbol O...
4)
3ClChlorine Chlorine Chlorine ( , from the Greek word 'χλωρóς' (khlôros, meaning 'pale green'), is the chemical element with atomic number 17 and symbol Cl. It is a halogen, found in the periodic table in group 17 (formerly VII, VIIa, or VIIb). As the chloride ion, which is part of common salt and...
, sometimes occurring in sufficient abundance to be mined as an
oreAn ore is a type of rock that contains minerals such as gemstones or metals that can be extracted through mining and refined for use. Samples of ore in the form of exceptionally beautiful crystals, exotic layering visible when sectioned or polished or metallic presentations such as large nuggets or...
of lead.
CrystalA crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is crystallography...
s are common, and have the form of a hexagonal prism terminated by the basal planes, sometimes combined with narrow faces of a hexagonal pyramid. Crystals with a barrel-like curvature are not uncommon. Globular and reniform masses are also found.
Pyromorphite is a
mineralA mineral is a naturally occurring solid formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure, and specific physical properties. A rock, by comparison, is an aggregate of minerals and/or mineraloids, and need not have a specific...
species composed of
leadLead is a main-group element with symbol Pb and atomic number 82. Lead is a soft, malleable poor metal, also considered to be one of the heavy metals. Lead has a bluish-white color when freshly cut, but tarnishes to a dull grayish color when exposed to air...
chlorophosphate:
PbLead is a main-group element with symbol Pb and atomic number 82. Lead is a soft, malleable poor metal, also considered to be one of the heavy metals. Lead has a bluish-white color when freshly cut, but tarnishes to a dull grayish color when exposed to air...
5(
PPhosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus is commonly found in inorganic phosphate rocks. Elemental phosphorus exists in two major forms - white phosphorus and red phosphorus...
OOxygen Oxygen Oxygen (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter) is the element with atomic number 8 and represented by the symbol O...
4)
3ClChlorine Chlorine Chlorine ( , from the Greek word 'χλωρóς' (khlôros, meaning 'pale green'), is the chemical element with atomic number 17 and symbol Cl. It is a halogen, found in the periodic table in group 17 (formerly VII, VIIa, or VIIb). As the chloride ion, which is part of common salt and...
, sometimes occurring in sufficient abundance to be mined as an
oreAn ore is a type of rock that contains minerals such as gemstones or metals that can be extracted through mining and refined for use. Samples of ore in the form of exceptionally beautiful crystals, exotic layering visible when sectioned or polished or metallic presentations such as large nuggets or...
of lead.
CrystalA crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is crystallography...
s are common, and have the form of a hexagonal prism terminated by the basal planes, sometimes combined with narrow faces of a hexagonal pyramid. Crystals with a barrel-like curvature are not uncommon. Globular and reniform masses are also found. It is part of a series with two other minerals:
mimetiteMimetite, whose name derives from the Greek mimethes, meaning "imitator", is an arsenate mineral which forms as a secondary mineral in lead deposits, usually by the oxidation of galena and arsenopyrite. The name is a reference to mimetite's resemblance to the mineral pyromorphite...
(Pb
5(
AsArsenic is the chemical element that has the symbol As, atomic number 33 and atomic mass 74.92. Arsenic was first documented by Albertus Magnus in 1250. Arsenic is a notoriously poisonous metalloid with many allotropic forms, including a yellow and several black and grey forms...
O
4)
3Cl) and
vanadiniteVanadinite is a mineral belonging to the apatite group of phosphates, with the chemical formula Pb53Cl. It is one of the main industrial ores of the metal vanadium and a minor source of lead. A dense, brittle mineral, it is usually found in the form of red hexagonal crystals...
(Pb
5(
VVanadium is the chemical element with the symbol V and atomic number 23. It is a soft, silvery grey, ductile transition metal. The formation of an oxide layer stabilizes the metal against oxidation. Andrés Manuel del Río discovered vanadium in 1801 by analyzing the mineral vanadinite, and named it...
O
4)
3Cl), the resemblance in external characters is so close that, as a rule, it is only possible to distinguish between them by chemical tests.
They were formerly confused under the names green lead ore and brown lead ore (German, Grünbleierz and Braunbleierz). The phosphate was first distinguished chemically by M. H. Kiaproth in 1784, and it was named pyromorphite by J. F. L. Hausmann in 1813.
The color of the mineral is usually some bright shade of green, yellow or brown, and the
lusterLustre is a description of the way light interacts with the surface of a crystal, rock, or mineral. For example, a diamond is said to have an adamantine lustre and pyrite is said to have a metallic lustre...
is resinous. The hardness is 3, and the specific gravity 6.5 - 7.1. Owing to isomorphous replacement of the
phosphorusPhosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus is commonly found in inorganic phosphate rocks. Elemental phosphorus exists in two major forms - white phosphorus and red phosphorus...
by
arsenicArsenic is the chemical element that has the symbol As, atomic number 33 and atomic mass 74.92. Arsenic was first documented by Albertus Magnus in 1250. Arsenic is a notoriously poisonous metalloid with many allotropic forms, including a yellow and several black and grey forms...
there may be a gradual passage from pyromorphite to mimetite. Varieties containing
calciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element by mass in the Earth's crust...
isomorphously replacing lead are lower in density (specific gravity 5.9 - 6.5) and usually lighter in color; they bear the names polysphaerite (because of the globular form), miesite from
MiesMies is a municipality in the district of Nyon in the canton of Vaud in Switzerland.It is approximately half-way between Geneva and Nyon. Mies sits on Lake Geneva , which lies to the southeast and is 410m above sea-level. The highest point of Mies is 455m above sea level. The part of Mies touching...
in
BohemiaBohemia is a historical region in central Europe, occupying the western two-thirds of the traditional Czech Lands, currently the Czech Republic...
, nussierite from Nuizière,
ChéneletteChénelette is a commune in the Rhône department in eastern France.-Geography:Chénelette is a small village of approximately 300 people located in the north-west of the Rhône Department, notably in the Beaujolais region. The surrounding landscape is one of forests, mountains , and pastures...
, near
BeaujeuBeaujeu is a commune of the Rhône department in eastern France.It lies between Mâcon and Lyon.Beaujeu gives its name to the famous wine region of Beaujolais , a former province of France of which it is the historical capital...
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RhôneRhône is a French department located in the central Eastern region of Rhône-Alpes. It is named after the Rhône River.- History :...
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FranceFrance , officially the French Republic , is a country located in Western Europe, with several overseas islands and territories located on other continents. Metropolitan France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean...
, and cherokine from
Cherokee CountyCherokee County is a county located in the U.S. state of Georgia. As of 2000, the population was 141,903. The 2007 Census Estimate placed the population at 204,363...
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GeorgiaGeorgia is a state in the United States. One of the original Thirteen Colonies that revolted against British rule in the American Revolution, it had been the last of the Thirteen Colonies to be established, in 1733. Georgia was the fourth state to ratify the United States Constitution, on January...
.