Loveringite is a rare metallic oxide mineral

Oxide mineral

The oxide mineral class includes those minerals in which the oxide anion is bonded to one or more metal ions. The hydroxide bearing minerals are typically included in the oxide class...

 of the crichtonite group with the chemical formula (Ca,Ce)(Ti,Fe,Cr,Mg)₂₁O₃₈. It is a late-stage magmatic mineral, formed in the residual melt of mafic

Mafic

Mafic is an adjective describing a silicate mineral or rock that is rich in magnesium and iron; the term is a portmanteau of the words "magnesium" and "ferric". Most mafic minerals are dark in color and the relative density is greater than 3. Common rock-forming mafic minerals include olivine,...

 layered intrusions in either the olivine

Olivine

The mineral olivine is a magnesium iron silicate with the formula 2SiO4. It is a common mineral in the Earth's subsurface but weathers quickly on the surface....

-chromite

Chromite

Chromite is an iron chromium oxide: FeCr2O4. It is an oxide mineral belonging to the spinel group. Magnesium can substitute for iron in variable amounts as it forms a solid solution with magnesiochromite ; substitution of aluminium occurs leading to hercynite .-Occurrence:Chromite is found in...

, pyroxene

Pyroxene

The pyroxenes are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. They share a common structure consisting of single chains of silica tetrahedra and they crystallize in the monoclinic and orthorhombic systems...

, or plagioclase

Plagioclase

Plagioclase is an important series of tectosilicate minerals within the feldspar family. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a solid solution series, more properly known as the plagioclase feldspar series...

-rich layers.

Discovery and occurrence

Loveringite was discovered in 1978 in the Jimberlana Intrusion, Dundas Shire, Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

, and was named for Australian geochemist and University of Melbourne

University of Melbourne

The University of Melbourne is a public university located in Melbourne, Victoria. Founded in 1853, it is the second oldest university in Australia and the oldest in Victoria...

 professor John Francis Lovering, in recognition of his work on fission-track methods in geochemistry

Geochemistry

The field of geochemistry involves study of the chemical composition of the Earth and other planets, chemical processes and reactions that govern the composition of rocks, water, and soils, and the cycles of matter and energy that transport the Earth's chemical components in time and space, and...

.

Loveringite has also been generally found in areas of medium-grade metamorphism, reported from the Hoggar Mountains of Algeria

Algeria

Algeria , officially the People's Democratic Republic of Algeria , also formally referred to as the Democratic and Popular Republic of Algeria, is a country in the Maghreb region of Northwest Africa with Algiers as its capital.In terms of land area, it is the largest country in Africa and the Arab...

; the
Hohe Tauern Mountains, Salzburg

Salzburg

-Population development:In 1935, the population significantly increased when Salzburg absorbed adjacent municipalities. After World War II, numerous refugees found a new home in the city. New residential space was created for American soldiers of the postwar Occupation, and could be used for...

, Austria

Austria

Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...

; the Koitelainen intrusion of Lappland

Lappland

Lappland can refer to:*Lapland, geographic region in Northern Fennoscandia* Lappland, Sweden* Lapland, FinlandUnlike the English word "Lapland", the Swedish word is not used to indicate the area specifically inhabited by the Sami people. An old Swedish word for the Sami area under Swedish control...

, Finland

Finland

Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

; Bourg d’Oisans, Isere, France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

; Bracco, Liguria

Liguria

Liguria is a coastal region of north-western Italy, the third smallest of the Italian regions. Its capital is Genoa. It is a popular region with tourists for its beautiful beaches, picturesque little towns, and good food.-Geography:...

, Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

; the Kerguelen Islands

Kerguelen Islands

The Kerguelen Islands , also known as the Desolation Islands, are a group of islands in the southern Indian Ocean constituting the emerged part of the otherwise submerged Kerguelen Plateau. The islands, along with Adélie Land, the Crozet Islands and the Amsterdam and Saint Paul Islands are part of...

; the Khibiny Massif

Khibiny Massif

The Khibiny Massif, Khibiny Mountains, Khibinsky Mountains or Khibins, Khibinsky tundras, Khibiny is one of the two main mountain ranges of the Kola Peninsula, Russia, within the Arctic Circle, located between Imandra and Umbozero lakes.The massif is of oval shape of about 1,300 sq.km...

 in the Kola Peninsula

Kola Peninsula

The Kola Peninsula is a peninsula in the far northwest of Russia. Constituting the bulk of the territory of Murmansk Oblast, it lies almost completely to the north of the Arctic Circle and is washed by the Barents Sea in the north and the White Sea in the east and southeast...

 of Russia

Russia

Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

; and the Masvingo District of Zimbabwe

Zimbabwe

Zimbabwe is a landlocked country located in the southern part of the African continent, between the Zambezi and Limpopo rivers. It is bordered by South Africa to the south, Botswana to the southwest, Zambia and a tip of Namibia to the northwest and Mozambique to the east. Zimbabwe has three...

.

Crystallography

Loveringite is trigonal rhombohedral in the hexagonal

Hexagonal crystal system

In crystallography, the hexagonal crystal system is one of the 7 crystal systems, the hexagonal lattice system is one of the 7 lattice systems, and the hexagonal crystal family is one of the 6 crystal families...

 class system, meaning it contains three equal axes each related by 120° and one axis perpendicular to these. It has a three-fold rotation axis as well as a center of symmetry and belongs to the space group R3. Loveringite is found to be grayish white to gray in plane polarized light and does not display pleochroism

Pleochroism

Pleochroism is an optical phenomenon in which a substance appears to be different colors when observed at different angles with polarized light.- Background :Anisotropic crystals will have optical properties that vary with the direction of light...

. Additionally, when viewed in plane polarized light, Loveringite is found to have high relief and has sharp grain boundaries, shows fractures and cleavages well, and sticks out above other minerals in the thin section. Reflectance data indicates that loveringite is anisotropic, showing properties of different values when measured in different directions.