Pseudobrookite 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 ...

titanium Titanium is a chemical element; it has symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ...

oxide mineral The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. Minerals with complex anion groups such as the sil ...

with formula: Fe₂TiO₅ or (Fe³⁺,Fe²⁺)₂(²⁺)O₅.

Discovery and occurrence

Pseudobrookite was first described in 1878 for an occurrence in Uroi Hill (Arany Hill),

Simeria Simeria (; ; ) is a town in Hunedoara County, Transylvania, Romania, and an important railway junction with a hump yard. Six villages are administered by the town: Bârcea Mare (''Nagybarcsa''), Cărpiniș (''Gyertyános''), Simeria Veche (''Óp ...

Hunedoara County Hunedoara County () is a county (''județ'') of Romania, in Transylvania, with its capital city at Deva, Romania, Deva. The county is part of the Danube–Criș–Mureș–Tisa Euroregion. Name In Hungarian language, Hungarian, it is known as , ...

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

. The name is from Greek ψευδής, for false, and brookite because of its misleading similar appearance to

brookite Brookite is the Orthorhombic crystal system, orthorhombic variant of titanium dioxide (TiO2), which occurs in four known natural Polymorphism (materials science), polymorphic forms (minerals with the same composition but different structure). The ...

. Pseudobrookite forms as pneumatolytic deposition and alteration within titanium-rich

volcanic rock Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and me ...

s such as

andesite Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomina ...

rhyolite Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture (geology), texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained matri ...

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

. It may be associated with

xenolith A xenolith ("foreign rock") is a rock (geology), rock fragment (Country rock (geology), country rock) that becomes enveloped in a larger rock during the latter's development and solidification. In geology, the term ''xenolith'' is almost exclusi ...

s contained in the volcanics. It also commonly occurs in lithophysae. It occurs associated with

hematite Hematite (), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of . ...

magnetite Magnetite is a mineral and one of the main iron ores, with the chemical formula . It is one of the iron oxide, oxides of iron, and is ferrimagnetism, ferrimagnetic; it is attracted to a magnet and can be magnetization, magnetized to become a ...

bixbyite Bixbyite is a manganese iron oxide mineral with chemical formula: . The iron/manganese ratio is quite variable and many specimens have almost no iron. It is a metallic dark black with a Mohs hardness of 6.0 – 6.5. It is a somewhat rare mineral ...

ilmenite Ilmenite is a titanium-iron oxide mineral with the idealized formula . It is a weakly magnetic black or steel-gray solid. Ilmenite is the most important ore of titanium and the main source of titanium dioxide, which is used in paints, printi ...

enstatite Enstatite is a mineral; the magnesium endmember of the pyroxene silicate mineral series enstatite (MgSiO3) – ferrosilite (FeSiO3). The magnesium rich members of the solid solution series are common rock-forming minerals found in igneous and m ...

- ferrosilite,

tridymite Tridymite is a high-temperature polymorphism (materials science), polymorph of silica and usually occurs as minute tabular white or colorless pseudo-hexagonal crystals, or scales, in cavities in felsic volcanic rocks. Its chemical formula is sili ...

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tet ...

sanidine Sanidine is the high temperature form of potassium feldspar with a general formula K(AlSi3O8). Sanidine is found most typically in felsic volcanic rocks such as obsidian, rhyolite and trachyte. Sanidine crystallizes in the monoclinic crystal sys ...

topaz Topaz is a silicate mineral made of aluminium, aluminum and fluorine with the chemical formula aluminium, Alsilicon, Sioxygen, O(fluorine, F, hydroxide, OH). It is used as a gemstone in jewelry and other adornments. Common topaz in its natural ...

spessartine Spessartine is a nesosilicate, manganese aluminium garnet species, Mn2+3Al2(SiO4)3. Gemological Institute of America, ''GIA Gem Reference Guide'' 1995, This mineral is sometimes mistakenly referred to as ''spessartite''. Spessartine's name is ...

beryl Beryl ( ) is a mineral composed of beryllium aluminium Silicate minerals#Cyclosilicates, silicate with the chemical formula Be3Al2(SiO3)6. Well-known varieties of beryl include emerald and Aquamarine (gem), aquamarine. Naturally occurring Hex ...

mica Micas ( ) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into fragile elastic plates. This characteristic is described as ''perfect basal cleavage''. Mica is co ...

cassiterite Cassiterite is a tin oxide mineral, SnO2. It is generally opaque, but it is translucent in thin crystals. Its luster and multiple crystal faces produce a desirable gem. Cassiterite was the chief tin ore throughout ancient history and remains ...

and

apatite Apatite is a group of phosphate minerals, usually hydroxyapatite, fluorapatite and chlorapatite, with high concentrations of Hydroxide, OH−, Fluoride, F− and Chloride, Cl− ion, respectively, in the crystal. The formula of the admixture of ...

. Occurrences include: *

Mayen Mayen () is a town in the Mayen-Koblenz, Mayen-Koblenz District of the Rhineland-Palatinate Federal State of Germany, in the eastern part of the Volcanic Eifel Region. As well as the main town, additional settlements include Alzheim, Kürrenberg, ...

in the

Eifel The Eifel (; , ) is a low mountain range in western Germany, eastern Belgium and northern Luxembourg. It occupies parts of southwestern North Rhine-Westphalia, northwestern Rhineland-Palatinate and the southern area of the German-speaking Com ...

district,

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

* Mont Dore, Puy-de-Dome,

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

Vesuvius Mount Vesuvius ( ) is a Somma volcano, somma–stratovolcano located on the Gulf of Naples in Campania, Italy, about east of Naples and a short distance from the shore. It is one of several volcanoes forming the Campanian volcanic arc. Vesuv ...

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

Jumilla Jumilla () is a town and a municipality in southeastern Spain. It is located in the north east of the Region of Murcia, close to the towns of Cieza and Yecla. According to the 2018 census, the town population was 25,547. Geography The munic ...

Murcia Province The Region of Murcia (, ; ; ) is an autonomous community of Spain located in the southeastern part of the Iberian Peninsula, on the Mediterranean coast. The region is in area and had a population of 1,511,251 as at the start of 2020. About a ...

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

* Faial and

São Miguel Island São Miguel Island (; ), nicknamed "The Green Island" (), is the largest and most populous island in the Portugal, Portuguese archipelago of the Azores. The island covers and has around 140,000 inhabitants, with 45,000 people residing in Ponta D ...

Azores The Azores ( , , ; , ), officially the Autonomous Region of the Azores (), is one of the two autonomous regions of Portugal (along with Madeira). It is an archipelago composed of nine volcanic islands in the Macaronesia region of the North Atl ...

Kilimanjaro Mount Kilimanjaro () is a dormant volcano in Tanzania. It is the highest mountain in Africa and the highest free-standing mountain above sea level in the world, at above sea level and above its plateau base. It is also the highest volcano i ...

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

; *

Reunion Island Reunion may refer to: * Class reunion * Family reunion Reunion, Réunion, Re-union, Reunions or The Reunion may also refer to: Places * Réunion, a French overseas department and island in the Indian Ocean * Reunion, Commerce City, Colorado, U ...

* the Thomas Range,

Juab County, Utah Juab County ( ) is a county in western Utah, United States. As of the 2020 United States census, the population was 11,786. Its county seat and largest city is Nephi. Juab County is part of the Provo– Orem, Utah Metropolitan Statisti ...

Crater Lake Crater Lake ( Klamath: ) is a volcanic crater lake in south-central Oregon in the Western United States. It is the main feature of Crater Lake National Park and is a tourist attraction for its deep blue color and water clarity. T ...

and Lemolo Lake,

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

* the

Black Range The Black Range (also called the Devil's Mountains or Sierra Diablo) is an igneous mountain range running north–south in Sierra, Grant, and Catron counties in southwest New Mexico, in the Southwestern United States. Description The range's ...

Sierra County, New Mexico Sierra County () is a county located in the U.S. state of New Mexico. As of the 2020 Census, the population was 11,576. Its county seat is Truth or Consequences. Geography According to the U.S. Census Bureau, the county has a total area of , ...

* Cerro los Remedios,

Durango Durango, officially the Free and Sovereign State of Durango, is one of the 31 states which make up the Political divisions of Mexico, 32 Federal Entities of Mexico, situated in the northwest portion of the country. With a population of 1,832,650 ...

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

References

{{Reflist Oxide minerals Orthorhombic minerals Minerals in space group 63