Bukovskyite (also known as "''clay of Kutná Hora''") is an

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

arsenate The arsenate is an ion with the chemical formula . Bonding in arsenate consists of a central arsenic atom, with oxidation state +5, double bonded to one oxygen atom and single bonded to a further three oxygen atoms. The four oxygen atoms orien ...

sulfate The sulfate or sulphate ion is a polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many ...

mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Mi ...

with formula: Fe₂(AsO₄)(SO₄)(OH)·7H₂O which forms nodules with a reniform (kidney-shaped) surface. Under a microscope, these nodules appear as a collection of minute needles similar to

gypsum Gypsum is a soft sulfate mineral composed of calcium sulfate Hydrate, dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, drywall and blackboard or sidewalk ...

. Some can be seen with the naked eye and occur inside the nodules. Bukovskyite was first described from pit heaps from the

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, where sulfate ores had been mined at Kank, north of

Kutná Hora Kutná Hora (; ) is a town in the Central Bohemian Region of the Czech Republic. It has about 22,000 inhabitants. The history of Kutná Hora is linked to silver mining, which made it a rich and rapidly developing town. The centre of Kutná Hora, i ...

Bohemia Bohemia ( ; ; ) is the westernmost and largest historical region of the Czech Republic. In a narrow, geographic sense, it roughly encompasses the territories of present-day Czechia that fall within the Elbe River's drainage basin, but historic ...

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

, and other old deposits in the vicinity. Only recently defined and acknowledged, it was approved by the

IMA IMA or Ima may refer to: Education * Indian Military Academy, Dehradun * Instituto Miguel Ángel, a school in Mexico City Galleries and museums * Indianapolis Museum of Art, Indiana, US * Institut du Monde Arabe, Paris, France * Islamic Mus ...

in 1969. Bukovskyite was collected a long time ago from the overgrown pit heaps by the inhabitants of Kutná Hora. It was used for poisoning fieldmice and other field vermin. This poisonous clay, known also by the place name as "clay of Kutná Hora"', was widely known and it was considered to be 'arsenic' (arsenic trioxide). In 1901 Antonín Bukovský (1865–1950), a

Czech Czech may refer to: * Anything from or related to the Czech Republic, a country in Europe ** Czech language ** Czechs, the people of the area ** Czech culture ** Czech cuisine * One of three mythical brothers, Lech, Czech, and Rus *Czech (surnam ...

chemist, who studied minerals of old pit heaps, proved it was an arsenate.

References

Mineralienatlas

Webmineral

External links

Iron(III) minerals Arsenate minerals Sulfate minerals Triclinic minerals {{sulfate-mineral-stub