Witherite is a barium carbonate

Barium carbonate

Barium carbonate , also known as witherite, is a chemical compound used in rat poison, bricks, ceramic glazes and cement.Witherite crystallizes in the orthorhombic system...

 mineral, Ba

Barium

Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. Its oxide is historically known as baryta but it reacts with...

C

Carbon

Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

O

Oxygen

Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

₃, in the aragonite

Aragonite

Aragonite is a carbonate mineral, one of the two common, naturally occurring, crystal forms of calcium carbonate, CaCO3...

 group. Witherite crystallizes in the orthorhombic system and virtually always is twinned

Crystal twinning

Crystal twinning occurs when two separate crystals share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals in a variety of specific configurations. A twin boundary or composition surface separates the two crystals....

. The mineral is colorless, milky white, grey, pale yellow, green, to pale brown. The specific gravity

Specific gravity

Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...

 is 4.3, which is high for a translucent mineral. It fluoresces

Fluorescence

Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation of a different wavelength. It is a form of luminescence. In most cases, emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation...

 light blue under both long and short-wave UV

Ultraviolet

Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

 light, and is phosphorescent

Phosphorescence

Phosphorescence is a specific type of photoluminescence related to fluorescence. Unlike fluorescence, a phosphorescent material does not immediately re-emit the radiation it absorbs. The slower time scales of the re-emission are associated with "forbidden" energy state transitions in quantum...

 under short-wave UV light.

Witherite forms in low-temperature hydrothermal environments. It is commonly associated with fluorite

Fluorite

Fluorite is a halide mineral composed of calcium fluoride, CaF2. It is an isometric mineral with a cubic habit, though octahedral and more complex isometric forms are not uncommon...

, celestine, galena

Galena

Galena is the natural mineral form of lead sulfide. It is the most important lead ore mineral.Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms...

, barite

Barite

Baryte, or barite, is a mineral consisting of barium sulfate. The baryte group consists of baryte, celestine, anglesite and anhydrite. Baryte itself is generally white or colorless, and is the main source of barium...

, calcite

Calcite

Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite. Aragonite will change to calcite at 380-470°C, and vaterite is even less stable.-Properties:...

 and aragonite

Aragonite

Aragonite is a carbonate mineral, one of the two common, naturally occurring, crystal forms of calcium carbonate, CaCO3...

. Witherite occurrences include: Cave-in-Rock, Illinois

Cave-In-Rock, Illinois

Cave-In-Rock is a village in Hardin County, Illinois, United States. Its principal feature and attraction is a large nearby cave on the banks of the Ohio River. Cave-in-Rock was originally a stronghold for outlaws including; river pirates and highwaymen, Samuel Mason and James Ford, tavern...

, USA; Alston Moor

Alston Moor

Alston Moor is an area of moorland and civil parish in Cumbria, England, based around the small town of Alston. The parish had a population of 2,156 at the 2001 census. As well as the town of Alston, the parish includes the villages of Garrigill and Nenthead, along with the hamlets of Nenthall,...

, Cumbria

Cumbria

Cumbria , is a non-metropolitan county in North West England. The county and Cumbria County Council, its local authority, came into existence in 1974 after the passage of the Local Government Act 1972. Cumbria's largest settlement and county town is Carlisle. It consists of six districts, and in...

, Anglezarke

Anglezarke

Anglezarke is a sparsely populated civil parish in the Borough of Chorley in Lancashire, England. It is dominated by reservoirs that were built to supply water to Liverpool, and a large expanse of moorland with evidence of Bronze Age settlements...

, Lancashire

Lancashire

Lancashire is a non-metropolitan county of historic origin in the North West of England. It takes its name from the city of Lancaster, and is sometimes known as the County of Lancaster. Although Lancaster is still considered to be the county town, Lancashire County Council is based in Preston...

 and Burnhope

Burnhope

Burnhope is a village and civil parish in County Durham, England. It is located in the Craghead valley on the opposite side to Stanley and has approximately 1200 inhabitants....

, County Durham

County Durham

County Durham is a ceremonial county and unitary district in north east England. The county town is Durham. The largest settlement in the ceremonial county is the town of Darlington...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

; Thunder Bay

Thunder Bay

-In Canada:Thunder Bay is the name of three places in the province of Ontario, Canada along Lake Superior:*Thunder Bay District, Ontario, a district in Northwestern Ontario*Thunder Bay, a city in Thunder Bay District*Thunder Bay, Unorganized, Ontario...

 area, Ontario

Ontario

Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

, Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 and Poland

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 (Tarnowskie Góry

Tarnowskie Góry

Tarnowskie Góry is a town in Silesia in southern Poland, near Katowice. Borders on the Upper Silesian Metropolitan Union - metropolis with the population of 2 millions. Located in the Silesian Highlands....

 and Tajno

Tajno Podjeziorne

Tajno Podjeziorne is a village in the administrative district of Gmina Bargłów Kościelny, within Augustów County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately south-east of Bargłów Kościelny, south-west of Augustów, and north of the regional capital Białystok.-References:...

 at Suwałki Region).

Witherite was named for William Withering

William Withering

William Withering was an English botanist, geologist, chemist, physician and the discoverer of digitalis.-Introduction:...

 (1741-1799) an English

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 physician and naturalist.

Risk to Human Health

The 18th century naturalist Dr. Leigh recorded its lethal

Lethal

Lethal is an adjective meaning capable of causing death.Lethal may also refer to:* Lethal , an American heavy metal band* Leigh Matthews, Australian rules footballer nicknamed "Lethal" or "Lethal" Leigh...

 effects after the death of a farmer's wife and child. James Watt Jnr. experimented with the mineral on animals and he recorded the same lethal properties. Until the 18th century farmers at Anglezarke

Anglezarke

Anglezarke is a sparsely populated civil parish in the Borough of Chorley in Lancashire, England. It is dominated by reservoirs that were built to supply water to Liverpool, and a large expanse of moorland with evidence of Bronze Age settlements...

 used the mineral as rat poison.

Industrial Use

Another experiment was conducted by Josiah Wedgwood

Josiah Wedgwood

Josiah Wedgwood was an English potter, founder of the Wedgwood company, credited with the industrialization of the manufacture of pottery. A prominent abolitionist, Wedgwood is remembered for his "Am I Not A Man And A Brother?" anti-slavery medallion. He was a member of the Darwin–Wedgwood family...

 who used it in his 'Jasper ware', the mineral had previously been considered as worthless.