Skip to content
Category

Uranium(VI) minerals

page 1
carnotite
thumb|Carnotite from the Happy Jack Mine, Moab, Utah
autunite
Autunite (hydrated calcium uranyl phosphate), with formula Ca(UO2)2(PO4)2·10–12H2O, is a yellow-greenish fluorescent phosphate mineral with a hardness of 2–. Autunite crystallizes in the orthorhombic system and often occurs as tabular square crystals, commonly in small crusts or in fan-like masses. Due to the moderate uranium content of 48.27% it is radioactive and also used as uranium ore. Autunite fluoresces bright green to lime green under UV light. The mineral is also called calco-uranite, but this name is rarely used and effectively outdated.
torbernite
Torbernite, also known as chalcolite, is a relatively common mineral with the chemical formula Cu[(UO2)(PO4)]2·12H2O. It is a radioactive, hydrated green copper uranyl phosphate, found in granites and other uranium-bearing deposits as a secondary mineral. The chemical formula of torbernite is similar to that of autunite in which a Cu2+ cation replaces a Ca2+ cation. Torbernite tends to dehydrate to metatorbernite with the sum formula Cu[(UO2)(PO4)]2·8H2O.
abernathyite
Abernathyite is a mineral with formula K(UO2)(AsO4)·3H2O. The mineral is named after Jesse Evrett Abernathy (1913–1963) who first noted it in 1953 in the U.S. State of Utah. It was described as a new mineral species in 1956. Abernathyite is yellow and occurs as small crystals.
uranophane
Uranophane (Ca(UO2)2(SiO3OH)2·5H2O), also known as uranotile, is a rare calcium uranium silicate hydrate mineral that forms from the oxidation of other uranium-bearing minerals. It has a yellow color and is radioactive.
tyuyamunite
Tyuyamunite (pronounced tuh-YOO-ya-moon-ite) is a very rare uranium mineral with formula Ca(UO2)2V2O8·(5–8)H2O. It is a member of the carnotite group. It is a bright, canary-yellow color because of its high uranium content. Also, because of tyuyamunite's high uranium content, it is radioactive. It was named by Konstantin Avtonomovich Nenadkevich, in 1912, after its type locality, Tyuya-Muyun, Fergana Valley, Kyrgyzstan.
curite
Curite is a rare mineral with the chemical composition Pb3[(UO2)4O4(OH)3]2·2 H2O. It is therefore a hydrated lead uranyl oxide, which forms red needles or orange, massive aggregates.
becquerelite
Becquerelite is a uranium mineral with the chemical formula: Ca(UO2)6O4(OH)6·8(H2O). It is a secondary mineral which contains calcium and is a bright yellow colour. It has a Mohs hardness of about 2.
boltwoodite
Boltwoodite is a hydrated uranyl silicate mineral with formula (K0.56Na0.42)[(UO2)(SiO3OH)]·1.5(H2O), distinct in crystal structure from sodium boltwoodite, which has an orthorhombic structure rather than monoclinic. It is formed from the oxidation and alteration of primary uranium ores. It takes the form of a crust on some sandstones that bear uranium. These crusts tend to be yellowish with a silky or vitreous luster.
rutherfordine
Rutherfordine is a mineral containing almost pure uranyl carbonate (UO2CO3). It crystallizes in the orthorhombic system in translucent lathlike, elongated, commonly radiating in fibrous, and in pulverulent, earthy to very fine-grained dense masses. It has a specific gravity of 5.7 and exhibits two directions of cleavage. It appears as brownish, brownish yellow, white, light brown orange, or light yellow fluorescent encrustations. It is also known as diderichite.
schoepite
Schoepite, empirical formula (UO2)8O2(OH)12·12(H2O) is a rare alteration product of uraninite in hydrothermal uranium deposits. It may also form directly from ianthinite. The mineral presents as a transparent to translucent yellow, lemon yellow, brownish yellow, or amber orthorhombic tabular crystals. Although over 20 other crystal forms have been noted; rarely in microcrystalline aggregates. When exposed to air schoepite converts over a short time to the metaschoepite form (UO3·H2O, ) within a few months of being exposed to ambient air.
billietite
Billietite is an uncommon mineral of uranium that contains barium. It has the chemical formula: Ba(UO2)6O4(OH)6•8H2O. It usually occurs as clear yellow orthorhombic crystals. Billietite is named after Valere Louis Billiet (1903–1945), Belgian crystallographer at the University of Ghent, Ghent, Belgium.
cuprosklodowskite
Cuprosklodowskite is a secondary uranium mineral formed by alteration of earlier uranium minerals. Its empirical formula is Cu(UO2)2(HSiO4)2·6(H2O). Cuprosklodowskite is a nesosilicate mineral, It is grass green to dark green in color, and its crystal habit is typically acicular, flat bladed crystals. It is a strongly radioactive mineral.
uranocircite
Uranocircite or Uranocircite-II is a uranium mineral with the chemical formula: Ba(UO2)2(PO4)2·10H2O. Uranocircite-I was discredited (the IMA-CMNMC published 'The New IMA List of Minerals', September 2012). It is a phosphate mineral which contains barium and is a green to yellow colour. It has a Mohs hardness of about 2.
studtite
Studtite, chemical formula [(UO2)O2(H2O)2]·2(H2O) or UO4·4(H2O), is a secondary uranium mineral containing peroxide produced by the alpha-radiolysis of water during its formation. It occurs as pale yellow to white needle-like crystals often in acicular, white sprays.
johannite
Johannite is a rare uranium sulfate mineral. It crystallizes in the triclinic crystal system with the chemical composition Cu[UO2(OH)SO4]2·8H2O. It crystallizes in the triclinic system and develops only small prism or thin to thick tabular crystals, usually occurs as flaky or spheroidal aggregates and efflorescent coatings. Its color is emerald-green to apple-green and its streak is pale green.
liebigite
Liebigite is a uranium carbonate mineral with the chemical formula: Ca2(UO2)(CO3)3·11H2O. It is a secondary mineral occurring in the oxidizing zone of uranium-bearing ores. It is green to yellow green in colour. It has a Mohs hardness of about 3. Liebigite, like some other uranium minerals, is fluorescent under UV light and is also translucent. It crystallizes in the orthorhombic system, but only rarely forms distinct crystals. It typically forms encrustations or granular aggregates.
sklodowskite
Sklodowskite is a uranium mineral with the chemical formula: Mg(UO2)2(HSiO4)2·5H2O. It is a secondary mineral which contains magnesium and is a bright yellow colour, its crystal habit is acicular, but can form in other shapes. It has a Mohs hardness of about 2–3. It is named after the maiden name of Marie Skłodowska Curie. It is the magnesium analogue of the much more common uranium mineral Cuprosklodowskite, which contains copper instead.
uranopilite
Uranopilite is a minor ore of uranium with the chemistry (UO2)6SO4(OH)6O2·14H2O or, hydrated uranyl sulfate hydroxide.
metatorbernite
Metatorbernite (or meta-torbernite) is a radioactive phosphate mineral, and is a dehydration pseudomorph of torbernite. Chemically, it is a copper uranyl phosphate and usually occurs in the form of green platy deposits. It can form by direct deposition from a supersaturated solution, which produces true crystalline metatorbernite, with a dark green colour, translucent diaphaneity, and vitreous lustre. However, more commonly, it is formed by the dehydration of torbernite, which causes internal stress and breakage within the crystal lattice, resulting in crystals composed of microscopic powder h
zippeite
Zippeite is a hydrous potassium uranium sulfate mineral with formula: K4(UO2)6(SO4)3(OH)10·4(H2O). It forms yellow to reddish brown monoclinic-prismatic crystals with perfect cleavage. The typical form is as encrustations and pulverulent earthy masses. It forms as efflorescent encrustations in underground uranium mines. It has a Mohs hardness of 2 and a specific gravity of 3.66. It is strongly fluorescent yellow under ultraviolet light and is moderately radioactive.
francevillite
Francevillite is a uranyl-group vanadate mineral in the tyuyamunite series. Its chemical formula is . Francevillite is a strongly radioactive mineral. It is typically orange, yellow or brownish yellow. It forms a series with curienite.
margaritasite
Margaritasite is a yellow, caesium-bearing mineral in the carnotite group. Its chemical formula is (Cs, K, H3O)2(UO2)2V2O8·H2O and its crystal system is monoclinic (space group P21/a).
fourmarierite
Fourmarierite is a secondary uranium-lead mineral. It was named for the Belgian geologist Paul Fourmarier (1877–1970). Its chemical formula is .
zeunerite
Zeunerite is a green copper uranium arsenate mineral with formula Cu(UO2)2(AsO4)2·(10-16)H2O. It is a member of the autunite group. The associated mineral metazeunerite is a dehydration product of zeunerite.
ulrichite
Ulrichite is a rare green uranium phosphate mineral (CaCu(UO2)[PO4]2·4H2O). It crystallizes as monoclinic prisms which occur as apple green acicular radiating clusters. It is radioactive and exhibits strong yellow fluorescence under ultraviolet radiation.
schröckingerite
Schröckingerite is a radioactive yellow uranium-containing carbonate mineral, hydrated sodium calcium uranyl sulfate carbonate fluoride. Schröckingerite crystallizes in the orthorhombic system, occurring as globular clusters, and fluoresces yellow-green under ultraviolet light.
saléeite
Saleeite is a secondary uranium mineral occurring in the oxidized zones of uranium deposits, or as disseminations in carnotite-bearing sandstones. Its chemical formula is Mg(UO2)2(PO4)2·10(H2O).
vanuralite
Vanuralite is a mineral of uranium with chemical formula: Al(UO2)2(VO4)2(OH)·11(H2O). It has yellow crystals and a Mohs hardness of 2. The name comes from the composition of the mineral.
bergenite
Bergenite is a rare uranyl phosphate of the more specific phosphuranylite group. The phosphuranylite-type sheet in bergenite is a new isomer of the group, with the uranyl phosphate tetrahedra varying in an up-up-down, same-same-opposite (uuduudSSOSSO) orientation. All bergenite samples have been found in old mine dump sites. Uranyl minerals are a large constituent of uranium deposits.
andersonite
Andersonite, Na2Ca(UO2)(CO3)3·6H2O, or hydrated sodium calcium uranyl carbonate is a rare uranium carbonate mineral that was first described in 1948. Named after Charles Alfred Anderson (1902–1990) of the United States Geological Survey, who first described the mineral species, it is found in sandstone-hosted uranium deposits. It has a high vitreous to pearly luster and is fluorescent. Andersonite specimens will usually glow a bright lemon yellow (or green with blue hints depending on the deposit) in ultraviolet light. It is commonly found as translucent small rhombohedral crystals that have a
phosphuranylite
Phosphuranylite is a uranyl phosphate mineral with formula KCa(H3O)3(UO2)7(PO4)4O4·8(H2O).
soddyite
Soddyite is a mineral of uranium. It has yellow crystals and usually mixed with curite in oxidized uranium ores. It is named after the British radiochemist and physicist Frederick Soddy (1877–1956). Soddyite has been a valid species since 1922, following its discovery in the locality of the Shinkolobwe uranium mine in the Haut-Katanga Province of the Democratic Republic of the Congo (DRC).
masuyite
Masuyite is a uranium/lead oxide mineral with formula Pb[(UO2)3O3(OH)2]·3H2O.
parsonsite
Parsonsite is a lead uranium phosphate mineral with chemical formula: Pb2(UO2)(PO4)2·2H2O. Parsonsite contains about 45% lead and 25% uranium. It forms elongated lathlike pseudo monoclinic crystals, radial spherulites, encrustations and powdery aggregates. It is of a light yellow colour. It has a Mohs hardness of 2.5-3 and a specific gravity of 5.72 - 6.29.
lepersonnite-(Gd)
Lepersonnite-(Gd) is a very rare uranium and rare-earth mineral with the chemical formula . It occurs with bijvoetite-(Y) in the Shinkolobwe deposit in the Democratic Republic of the Congo, famous for rare uranium minerals. It was the first confirmed mineral with essential gadoliniumGadolinium: The mineralogy of gadolinium - Mindat. org and remained the only gadolinium dominant species until the description of Monazite-(Gd) in 2023.
heinrichite
Heinrichite is a monoclinic-prismatic containing arsenic, barium, hydrogen, oxygen, and uranium. The mineral is named after Eberhardt William Heinrich (1918–1991) who first noted it in 1958 in the U.S. State of Oregon.
weeksite
Weeksite is a naturally occurring uranium silicate mineral with the chemical formula: K2(UO2)2Si6O15•4(H2O), potassium uranyl silicate. Weeksite has a Mohs hardness of 1–2. It was named for USGS mineralogist Alice Mary Dowse Weeks (1909–1988).
marthozite
Marthozite is an orthorhombic mineral that has a general formula of Cu(UO2)3(SeO3)3(OH)2·7H2O. It was named after Belgian mineralogist Aimé Marthoz (1894–1962), former Director-general of the Union Minière du Haut Katanga (UMHK).
guilleminite
Guilleminite (Ba(UO2)3(SeO3)2(OH)4·3H2O) is a uranium mineral named by R. Pierrot, J. Toussaint, and T. Verbeek in 1965 in honor of Jean Claude Guillemin (1923–1994), a chemist and mineralogist. It is a rare uranium/selenium mineral found at the Musonoi Mine in the Katanga Province of the Democratic Republic of the Congo.
sengierite
Sengierite is a rare oxide and hydroxide mineral, chemically a copper and uranyl vanadate, belonging to the carnotite group. Its chemical formula is Cu2(OH)2[UO2VO4]2·6H2O.
metazeunerite
Metazeunerite is an arsenate mineral with a chemical formula of Cu(UO2)2(AsO4)2·8H2O. The origin of this mineral is almost always from the natural dehydration process of zeunerite.
bayleyite
Bayleyite is a uranium carbonate mineral with the chemical formula: Mg2(UO2)(CO3)3·18(H2O). It is a secondary mineral which contains magnesium, uranium and carbon. It is a bright yellow color. Its crystal habit is acicular but is more commonly found as crusts on uranium bearing ores. It has a Mohs hardness of about 2–2.5.
demesmaekerite
Demesmaekerite is a rare uranium selenite mineral with the chemical formula: Pb2Cu5(UO2)2(SeO3)6(OH)6·2H2O.
derriksite
Derriksite is a very rare uranium mineral with the chemical formula Cu4(UO2)(SeO3)2(OH)6•H2O. It is a secondary mineral that contains copper, uranium and the rarer selenium. It is a bright green to duller bottle green colour. Its crystal habit is acicular, it is most likely to be found along with the uranyl selenium mineral demesmaekerite, but derriksite is much rarer than demesmaekerite. It is named after Jean Marie Francois Joseph Derriks (1912–1992), geologist and administrator of the Union Minière du Haut Katanga (UMHK). It has a Mohs hardness of about 2.
upalite
Upalite (Al(UO2)3(PO4)2O(OH)·7H2O) is a mineral found in the Democratic Republic of Congo. It is named after uranium, phosphorus and aluminium. Its type locality is Kobokobo pegmatite, Mwenga, Sud-Kivu, Democratic Republic of Congo.
althupite
Althupite (IMA symbol: Ahp) is a rare aluminium thorium uranyl phosphate mineral with complex formula written as AlTh(UO2)7(PO4)4O2(OH)5·15H2O, from a granitic pegmatite. It is named after its composition (ALuminium, THorium, Uranium, and Phosphorus).
mundite
Mundite is a uranium phosphate mineral with chemical formula: Al(UO2)3(PO4)2(OH)3·5(H2O). It contains aluminium and has a yellow tinge to it. It usually appears on sandstones or limestones.
arsenuranospathite
Arsenuranospathite (IMA symbol: Aush) is a rare mineral with the chemical formula Al(UO2)2(AsO4)2F·20H2O. The name "arsenuranospathite" as arsenate analog of uranospathite was first used by Walenta (1963) with reference to a uranyl-arsenate mineral from Black Forest (Schwarzwald) massif, Germany. thumb|Arsenuranospathite Later it was undoubtedly demonstrated that the name arsenuranospathite was applied, at least, to two different species – proper arsenuranospathite, ideally Al(UO2)2(AsO4)2F·20H2O, orthorhombic, and its partially dehydrated analogue, Al(UO2)2(AsO4)2F·nH2O (n = 8–10), tetragonal
astrocyanite-(Ce)
Astrocyanite-(Ce) is a bright blue mineral with the chemical formula . Its type locality is Kamoto East Open Cut, Kamoto, Kolwezi, Lualaba, Congo
albrechtschraufite
Albrechtschraufite (IMA symbol: Asf) is a very rare complex hydrated calcium and magnesium-bearing uranyl fluoride carbonate mineral with formula Ca4Mg(UO2)2(CO3)6F2·17H2O. Its molar weight is 1,428.98 g, color yellow-green, streak white, density 2.6 g/cm3, Mohs hardness 2–3, and luster is vitreous (glassy). It is named after Albrecht Schrauf (1837–1897), Professor of Mineralogy, University of Vienna. Its type locality is Jáchymov, Jáchymov District, Krušné Hory Mountains, Karlovy Vary Region, Bohemia, Czech Republic.
gauthierite
Gauthierite is a very rare mineral with the idealised chemical sum formula . It is a radioactive, hydrated orange-coloured lead potassium uranyl oxide hydroxide. It was found by analysing old mineral specimens, and is only known from one locality, the Shinkolobwe Mine in the Democratic Republic of the Congo. The mineral was named in honour of Gilbert Gauthier, a Belgian collector of uranium minerals, who provided a sample to one of the co-authors of the study that first identified it in 2017.
haiweeite
Haiweeite is a mineral of uranium and has the chemical formula: Ca[(UO2)2Si5O12(OH)2]·3(H2O). It is a secondary mineral of uranium, a product of oxidation. It has a greenish yellow color. It has a Mohs hardness of about 3.5 and is fluorescent under UV light.
braunerite
Braunerite is a hydrous uranyl carbonate mineral discovered by Jakub Plášil of the Institute of Physics at the Academy of Sciences of the Czech Republic and colleagues in the Svornost mine in the Jáchymov ore district, Western Bohemia, Czech Republic.
coconinoite
Coconinoite is a uranium ore that was discovered in Coconino County, Arizona. It is a phosphate mineral; or uranyl phosphate mineral along with other subclass uranium U6+ minerals like blatonite, boltwoodite, metazeunerite and rutherfordine.
sayrite
thumb | right | Orange crystals of sayrite. Sayrite (Pb2(UO2)5O6(OH)24(H2O)) is an alteration product of uraninite named after the X-ray crystallographer David Sayre. Sayrite contains hydrogen, oxygen, uranium and lead. It is mined at Shinkolobwe Mine, (Kasolo Mine), Kambove District, Haut-Katanga, Democratic Republic of the Congo. It is usually orange in color but also can be reddish and yellowish and is in the monoclinic crystal system.
fermiite
Fermiite is a rare uranium mineral with the formula Na4(UO2)(SO4)3·3H2O. Chemically related minerals include oppenheimerite, meisserite (which is also structurally-related to fermiite), belakovskiite, natrozippeite and plášilite. Fermiite comes from the Blue Lizard mine, San Juan County, Utah, USA, which is known for many rare uranium minerals. The name honors Enrico Fermi (1901–1954).
belakovskiite
Belakovskiite is a very rare uranium mineral with the formula Na7(UO2)(SO4)4(SO3OH)(H2O)3. It is interesting in being a natural uranyl salt with hydrosulfate anion, a feature shared with meisserite. Other chemically related minerals include fermiite, oppenheimerite, natrozippeite and plášilite. Most of these uranyl sulfate minerals was originally found in the Blue Lizard mine, San Juan County, Utah, US. The mineral is named after Russian mineralogist Dmitry Ilych Belakovskiy.
bijvoetite-(Y)
Bijvoetite-(Y) is a very rare rare-earth and uranium mineral with the formula (Y,REE)8(UO2)16(CO3)16O8(OH)8·39H2O. When compared to the original description, the formula of bijvoetite-(Y) was changed in the course of crystal structure redefinition. Bijvoetite-(Y) is an example of natural salts containing both uranium and yttrium, the other examples being kamotoite-(Y) and sejkoraite-(Y). Bijvoetite-(Y) comes from Shinkolobwe deposit in Republic of Congo, which is famous for rare uranium minerals. The other interesting rare-earth-bearing uranium mineral, associated with bijvoetite-(Y), is leper
meisserite
Meisserite is a very rare uranium mineral with the formula Na5(UO2)(SO4)3(SO3OH)(H2O). It is interesting in being a natural uranyl salt with hydrosulfate (hydroxysulfate) anion, a feature shared with belakovskiite. Other chemically related minerals include fermiite, oppenheimerite, natrozippeite and plášilite. Most of these uranyl sulfate minerals was originally found in the Blue Lizard mine, San Juan County, Utah, USA. The mineral is named after Swiss mineralogist Nicolas Meisser.