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Minerals in space group 58

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andalusite
Andalusite is an aluminium nesosilicate mineral with the chemical formula Al2SiO5. This mineral was called andalousite by Delamétherie, who thought it came from Andalusia, Spain. It soon became clear that it was a locality error, and that the specimens studied were actually from El Cardoso de la Sierra, in the Spanish province of Guadalajara, not Andalusia.
marcasite
The mineral marcasite, sometimes called "white iron pyrite", is iron sulfide (FeS2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both structures contain the disulfide S22− ion, having a short bonding distance between the sulfur atoms. The structures differ in how these di-anions are arranged around the Fe2+ cations. Marcasite is lighter and more brittle than pyrite. Specimens of marcasite often crumble and break up due to the unstable crystal structure.
adamite
Adamite is a zinc arsenate hydroxide mineral, Zn2AsO4OH. It is a mineral that typically occurs in the oxidized or weathered zone above zinc ore occurrences. Pure adamite is colorless, but usually it possess yellow color due to Fe compounds admixture. Tints of green also occur and are connected with copper substitutions in the mineral structure. Olivenite is a copper arsenate that is isostructural with adamite and there is considerable substitution between zinc and copper resulting in an intermediate called cuproadamite. Zincolivenite is an intermediate mineral with formula CuZn(AsO4)(OH). Mang
löllingite
Loellingite, also spelled löllingite, is an iron arsenide mineral with formula FeAs2. It is often found associated with arsenopyrite (FeAsS) from which it is hard to distinguish. Cobalt, nickel and sulfur substitute in the structure. The orthorhombic lollingite group includes the nickel iron arsenide rammelsbergite and the cobalt iron arsenide safflorite. Leucopyrite is an old synonym for loellingite.
mullite
Mullite or porcelainite is a rare silicate mineral formed during contact metamorphism of clay minerals. It can form two stoichiometric forms: 3Al2O32SiO2 or 2Al2O3 SiO2. Unusually, mullite has no charge-balancing cations present. As a result, there are three different aluminium sites: two distorted tetrahedral and one octahedral.
libethenite
Libethenite is a rare copper phosphate hydroxide mineral. It forms striking, dark green orthorhombic crystals. It was discovered in 1823 in Ľubietová, Slovakia and is named after the German name of that locality (Libethen). Libethenite has also been found in the Miguel Vacas Mine, Conceição, Vila Viçosa, Évora District, Portugal, and in Tier des Carrières, Cahai, Vielsaim, Stavelot Massif, Luxembourg Province, Belgium.
safflorite
Safflorite is a rare cobalt iron arsenide mineral with the chemical formula . Pure safflorite is , but iron is virtually always present. Safflorite is a member of the three-way substitution series of arsenides known as the loellingite group. More than fifty percent iron makes the mineral loellingite whereas more than fifty percent nickel and the mineral is rammelsbergite. A parallel series of antimonide minerals exist.
rammelsbergite
Rammelsbergite is a nickel arsenide mineral with formula NiAs2. It forms metallic silvery to tin white to reddish orthorhombic prismatic crystals, and is usually massive in form. It has a Mohs hardness of 5.5 and a specific gravity of 7.1.
ferroselite
Orthorhombic ferroselite and its isometric polymorph dzharkenite are iron selenides of general formula FeSe2 precipitated under reducing conditions in anoxic environments. They are a source of selenium in the Rocky Mountains where selenium occurrence is associated with Upper Cretaceous shale deposits.
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.
moolooite
Moolooite is a rare blue-green mineral with the formula Cu(C2O4)·n(H2O) (n<1) (copper(II) oxalate hydrate). It was discovered in Bunbury Well, Mooloo Downs station, Murchison, Western Australia in 1986. It has an orthorhombic crystalline structure, and is formed by the interaction of bird guano with weathering copper sulfides.
kobellite
Kobellite is a gray, fibrous, metallic mineral with the chemical formula . It is also a sulfide mineral consisting of antimony, bismuth, and lead. It is a member of the izoklakeite – berryite series with silver and iron substituting in the copper site and a varying ratio of bismuth, antimony, and lead. It crystallizes with monoclinic pyramidal crystals. The mineral can be found in ores and deposits of Hvena, Sweden; Ouray, Colorado; and Wake County, North Carolina, US. The mineral was named after Wolfgang Franz von Kobell (1803–1882), a German mineralogist.
zincolivenite
Zincolivenite is a copper zinc arsenate mineral with formula CuZn(AsO4)(OH) that is a member of the olivenite group. Its colors range from green to blue, and its name comes from its composition of zinc and olivenite.
eveite
Eveite is a manganese arsenate mineral in the olivenite group. Its chemical formula is Mn2AsO4OH. It is found only in Långban, Filipstad, Värmland, Sweden and at the Sterling Mine in New Jersey, United States. It is a dimorph of sarkinite and is isostructural with adamite. The name, for the biblical "Eve", comes from its structural similarities to adamite and is also a reference to its apple-green color. It can also be pale yellow. Eveite is an orthorhombic mineral, which means it has three crystallographic axes of unequal lengths which are at 90° to one another.
guyanaite
Guyanaite, CrO(OH), is a chromium oxide mineral that forms as an intergrowth with other chromium oxide minerals known as bracewellite (CrO(OH)) and grimaldiite (CrO(OH)) as well as eskolaite (Cr2O3) which in early findings were nearly indistinguishable from one another. These oxides formed so closely as intergrowths with one another that they were initially, and erroneously, identified as a single definite mineral previously known as merumite. Because of its complex history and the previously undiscovered nature of these chromium oxide polymorphs, the relevance of any information found in many