Železná hůrka () is an extinct

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the ...

volcano A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most oft ...

and a national nature monument in the

Fichtel Mountains The Fichtel Mountains (, ; ) is a mountain range in Germany and the Czech Republic. They extend from the valley of the Red Main River in northeastern Bavaria to the Karlovy Vary Region in western Czech Republic. The Fichtel Mountains contain an ...

in the

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 ...

Location

Železná hůrka is located about 1 km south of Mýtina in the Lipová municipality, in

Cheb District Cheb District () is a Okres, district in the Karlovy Vary Region of the Czech Republic. Its capital is the town of Cheb. It is the westernmost district of the Czech Republic. Administrative division Cheb District is divided into three Districts of ...

in the

Karlovy Vary Region The Karlovy Vary Region () is an administrative unit () of the Czech Republic, located in the westernmost part of the country. It is named after its capital Karlovy Vary. It is known for spas, which include Karlovy Vary and Mariánské Lázně. ...

of the Czech Republic. It lies in the easternmost part of the

. The area has also other manifestations of volcanic activity. Another Quaternary volcano, Komorní hůrka, is located nearby. CO₂ outgassing occurs in the area.

Metallic iron

The name means "iron hill" in Czech. Fragments of metallic iron are found in the local basalt deposits. Iron usually occurs on Earth only in the oxidized form, as iron ore, and needs to be processed into metallic iron by

smelting Smelting is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product. It is a form of extractive metallurgy that is used to obtain many metals such as iron-making, iron, copper extraction, copper ...

. It is thought that in the Železná hůrka area, iron-rich magma entered coal deposits which caused iron compounds to be reduced to metallic iron, in a process similar to

used by humans, but natural in origin. This kind of metallic iron from geological processes is rare on Earth (though it has been found in places including

Disko Island Disko Island (, ) is a large island in Baffin Bay, off the west coast of Greenland. It has an area of ,volcanic cone Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and s ...

consists of pyroclastic material deposited in discontinuous eruptions, with visible layering. At least the earliest of these eruptions were

phreatomagmatic Phreatomagmatic eruptions are volcanic eruptions resulting from interaction between magma and water. They differ from exclusively magmatic eruptions and phreatic eruptions. Unlike phreatic eruptions, the products of phreatomagmatic eruptions conta ...

, caused by contact of groundwater with hot magma; they deposited brownish layers of material which contains low-porosity hydroclasts, as well as fragments of the host rock (old rock crushed and carried away by the eruption) with oxidized surfaces. Then came another kind of volcanic (magmatic) activity, with less developed layering, which deposited black to dark-brown (melanephelinitic), slightly welded material, which contains fragments and blocks of porous lava, larger chunks of solidified lava known as

volcanic bomb A volcanic bomb or lava bomb is a mass of partially molten rock (tephra) larger than 64 mm (2.5 inches) in diameter, formed when a volcano ejects viscous fragments of lava during an eruption. Because volcanic bombs cool after they l ...

s, and smaller fragments known as

lapilli Lapilli (: lapillus) is a size classification of tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts. ''Lapilli'' is Latin for "little stones". By definition lapilli range from in dia ...

Mýtina maar

A funnel-shaped dry depression, located less than two kilometres from Železná hůrka, was confirmed to be a volcanic

maar A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma). A maar characteristically fills with water to form a relatively shallow ...

in 2008. This was the first maar discovered in Central Europe north of Alps and east of

Volcanic Eifel The Volcanic Eifel or Vulkan Eifel () consists of three areas of volcanic activity, known as the West Eifel, High Eifel, and East Eifel volcanic fields. Volcanic Eifel is a region in the Eifel Mountains in Germany that is defined to a large e ...

References

{{Authority control Protected areas of the Czech Republic Cheb District Volcanoes of the Czech Republic