Bournonite is a

sulfosalt Sulfosalt minerals are sulfide minerals with the general formula , where *A represents a metal such as copper, lead, silver, iron, and rarely mercury, zinc, vanadium *B usually represents semi-metal such as arsenic, antimony, bismuth, and rarely ...

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...

species, trithioantimoniate of

lead Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...

and

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...

with the formula PbCuSbS₃. It was first mentioned by Philip Rashleigh in 1797 as an

ore Ore is natural rock or sediment that contains one or more valuable minerals, typically containing metals, that can be mined, treated and sold at a profit.Encyclopædia Britannica. "Ore". Encyclopædia Britannica Online. Retrieved 7 Apr ...

antimony Antimony is a chemical element with the symbol Sb (from la, stibium) and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Antimony compounds have been known since ancient t ...

and was more completely described in 1804 by French crystallographer and

mineralogist Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proce ...

Jacques Louis, Comte de Bournon Jacques-Louis, Comte de Bournon FRS, FGS (21 January 1751 – 24 August 1825) was a French soldier and mineralogist who came to England after the French Revolution. He gained prominence in the scientific community, being elected a fellow of ...

(1751–1825), after whom it was named. The name given by Bournon himself (in 1813) was endellione, since used in the form endellionite, after

St Endellion St Endellion ( kw, Sen Endelyn) is a civil parish and hamlet in north Cornwall, England, United Kingdom. The hamlet and parish church are situated four miles (6.5 km) north of Wadebridge. The parish takes its name from Saint Endelienta, who ...

, the locality in

Cornwall Cornwall (; kw, Kernow ) is a historic county and ceremonial county in South West England. It is recognised as one of the Celtic nations, and is the homeland of the Cornish people. Cornwall is bordered to the north and west by the Atlantic ...

where the mineral was first found. The crystals are orthorhombic, and are generally tabular in

habit A habit (or wont as a humorous and formal term) is a routine of behavior that is repeated regularly and tends to occur subconsciously.

owing to the predominance of the basal pinacoid; numerous smooth bright faces are often developed on the edges and corners of the crystals. They are usually twinned, the twin-plane being a face of the prism (m); the angle between the faces of this prism being nearly a right angle (86° 20′), the twinning gives rise to cruciform groups and when it is often repeated the group has the appearance of a cog-wheel, hence the name ''Rãdelerz'' (wheel-ore) of the Kapnik miners. The repeated twinning gives rise to twin-lamellae, which may be detected on the fractured surfaces, even of the massive material. It is a mineral in medium temperature

hydrothermal Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with th ...

vein Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenat ...

deposits. It commonly occurs with galena,

tetrahedrite Tetrahedrite is a copper antimony sulfosalt mineral with formula: . It is the antimony endmember of the continuous solid solution series with arsenic-bearing tennantite. Pure endmembers of the series are seldom if ever seen in nature. Of the two, ...

, sphalerite,

chalcopyrite Chalcopyrite ( ) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mo ...

pyrite The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic luster and pale brass-yellow hue giv ...

stibnite Stibnite, sometimes called antimonite, is a sulfide mineral with the formula Sb2 S3. This soft grey material crystallizes in an orthorhombic space group. It is the most important source for the metalloid antimony. The name is derived from the ...

zinkenite Zinkenite is a steel-gray metallic sulfosalt mineral composed of lead antimony sulfide Pb9 Sb22 S42. Zinkenite occurs as acicular needle-like crystals. It was first described in 1826 for an occurrence in the Harz Mountains, Saxony-Anhalt, Germa ...

siderite Siderite is a mineral composed of iron(II) carbonate (FeCO3). It takes its name from the Greek word σίδηρος ''sideros,'' "iron". It is a valuable iron mineral, since it is 48% iron and contains no sulfur or phosphorus. Zinc, magnesium and ...

quartz Quartz is a hard, crystalline mineral composed of silica ( silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical ...

rhodochrosite Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO3. In its (rare) pure form, it is typically a rose-red color, but impure specimens can be shades of pink to pale brown. It streaks white, and its Mohs hardness varies bet ...

dolomite Dolomite may refer to: *Dolomite (mineral), a carbonate mineral *Dolomite (rock), also known as dolostone, a sedimentary carbonate rock *Dolomite, Alabama, United States, an unincorporated community *Dolomite, California, United States, an unincor ...

and barite. It was first described for an occurrence in Wheal Boys in the parish of

in Cornwall, it was found associated with

jamesonite Jamesonite is a sulfosalt mineral, a lead, iron, antimony sulfide with formula Pb4FeSb6S14. With the addition of manganese it forms a series with benavidesite.http://rruff.geo.arizona.edu/doclib/hom/jamesonite.pdf Handbook of Mineralogy It is a ...

, sphalerite and

. Later, still better crystals were found in another Cornish mine, namely, Herodsfoot mine near

Liskeard Liskeard ( ; kw, Lyskerrys) is a small ancient stannary and market town in south-east Cornwall, South West England. It is situated approximately 20 miles (32 km) west of Plymouth, west of the Devon border, and 12 miles (20 km) eas ...

, which was worked for

argentiferous galena Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It cry ...

. Fine crystals of large size have been found with

and siderite in the mines at Neudorf in the

Harz The Harz () is a highland area in northern Germany. It has the highest elevations for that region, and its rugged terrain extends across parts of Lower Saxony, Saxony-Anhalt, and Thuringia. The name ''Harz'' derives from the Middle High German ...

, and with sphalerite and

at Cavnic near

Baia Mare Baia Mare ( , ; hu, Nagybánya; german: Frauenbach or Groß-Neustadt; la, Rivulus Dominarum) is a municipality along the Săsar River, in northwestern Romania; it is the capital of Maramureș County. The city lies in the region of Maramur ...

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central, Eastern, and Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, Serbia to the southwest, Moldova to the east, and ...

. It has been reported from a large number of other localities.http://www.mindat.org/show.php?id=741&ld=1#themap Mindat with location data

References

{{Commons Lead minerals Copper(I) minerals Sulfosalt minerals Antimony minerals Orthorhombic minerals Minerals in space group 31