Carrollite

Last updated
Carrollite
Carrollite02.jpg
Carrollite from Kambove, Katanga. This specimen is 4.3 cm wide, with a 1.2 cm carrollite crystal partly covered by pyrite, between calcite crystals.
General
Category Sulfide mineral
Thiospinel group (Spinel structural group)
Formula
(repeating unit)
CuCo2S4
IMA symbol Cli [1]
Strunz classification 2.DA.05
Dana classification2.10.1.2
Crystal system Isometric
Crystal class Hexoctahedral (m3m)
H-M symbol: (4/m 3 2/m)
Space group Fd3m
Identification
ColorLight to dark gray, rarely tarnishes to copper red or violet gray
Crystal habit Octahedral and cubic crystals, also massive, granular or compact
Twinning {111} Polysynthetic or spinel twins [2]
Cleavage Imperfect on {001}
Fracture Conchoidal, subconchoidal or uneven
Tenacity Very brittle
Mohs scale hardness4.5 to 5.5
Luster Metallic
Streak Grey black
Diaphaneity Opaque. R is 43% to 45% for lambda = 560 nm [3]
Specific gravity 4.5 to 4.8 measured, 4.83 calculated
Refractive index n is not determined for an opaque mineral
Solubility Minerals of the linneite group are partly etched by nitric acid, with slight effervescence. [2]
Other characteristicsNot radioactive, not fluorescent
References [4] [5] [6] [7]

Carrollite, CuCo2S4, is a sulfide of copper and cobalt, often with substantial substitution of nickel for the metal ions, and a member of the linnaeite group. It is named after the type locality in Carroll County, Maryland, US, at the Patapsco mine, Sykesville. [6]

Contents

Unit cell

Space group: Fd3m. Unit cell parameters = a = 9.48  Å, Z = 8. Unit cell volume: V = 851.97 Å3 (calculated from unit cell parameters). [8]

Linnaeite group

Carrollite from Katanga, specimen 11 x 6 cm Carrollite.jpg
Carrollite from Katanga, specimen 11 × 6 cm

The linnaeite group is a group of sulfides and selenides with the general formula AB2X4 in which X is sulfur or selenium, A is divalent Fe, Ni, Co or Cu and B is trivalent Co, Ni or, for daubréelite, Cr. The minerals are isometric, space group Fd3m and isostructural with each other and with minerals of the spinel group.

The structure of the linnaeite group consists of a cubic close packed array of X (X is oxygen in the spinels and sulfur or selenium in the linnaeite group). Within the array of Xs there are two types of interstices, one type tetrahedrally co-ordinated and one type octahedrally co-ordinated. One eighth of the tetrahedral sites A are typically occupied by 2+ cations, and half of the octahedral sites B by 3+ cations. [9] Charnock et al. confirmed that carrollite contains Cu wholly within the tetrahedral sites. [10] Thus, the ideal formula one would expect for a spinel like carrollite is Cu2+Co3+2S2−4, but as in the case of copper sulfides in general the oxidation state of the copper atom is 1+, not 2+. An assignment of valences as Cu+Co3+2S1.75−4 is more appropriate; this was confirmed in a study of 2009. [11] The one missing electron per four sulfur atoms is delocalized, leading to metallic conductivity and even superconductivity at very low temperatures, combined with a complicated magnetic behavior. [12]

Solid solutions

A solid solution results when one cation can substitute for another across an appreciable composition range. In carrollite Co2+ can substitute for Cu+ at the A sites, and when the substitution is complete the mineral formed is called linnaeite, Co2+Co3+2S4. This means that there is a solid solution series between carrollite and linnaeite. Also, Ni substitutes for both Co and Cu in the carrollite structure, [13] giving a solid solution from carrollite to cuprian siegenite. Siegenite, Co2+Ni3+2S4, is itself a member of the solid solution series between linnaeite and polydymite, Ni2+Ni3+2S4. (Wagner and Cook found no evidence for solid solution between carrollite and fletcherite, CuNi2S4).

Environment

Carrollite occurs in hydrothermal vein deposits [14] associated with tetrahedrite, chalcopyrite, bornite, digenite, djurleite, chalcocite, pyrrhotite, pyrite, sphalerite, millerite, gersdorffite, ullmannite, cobaltoan calcite, and with linnaeite group members linnaeite, siegenite and polydymite.

Phase relations in the Cu-Co-S system have been investigated. [15] At temperatures around 900 °C a chalcocite-digenite solid solution coexists with cobalt sulfides. With decreasing temperature, at 880 °C a carrollite-linnaeite solid solution develops, becoming more copper-rich on cooling, with the carrollite composition at about 500 °C. Below 507 °C covellite is stable and coexists with copper-bearing cattierite. Low chalcocite appears at 103 °C, djurleite appears at 93 °C, and digenite disappears and anilite appears around 70 °C. There is some evidence for supergene replacement of an intermediate member of the linnaeite-carrollite series by djurleite. [15]

Distribution

Carrollite and native copper on calcite Carollite and native copper.jpg
Carrollite and native copper on calcite

Carrollite is found worldwide; reported in Australia, Austria, Azerbaijan, Brazil, Bulgaria, Canada, Chile, China, the Czech Republic, the Democratic Republic of Congo, [16] France, Germany, Japan, Morocco, Namibia, North Korea, Norway, Oman, Poland, Romania, Russia, Slovakia, Sweden, Switzerland, US and Zambia. [6]

Related Research Articles

<span class="mw-page-title-main">Pentlandite</span> Iron–nickel sulfide

Pentlandite is an iron–nickel sulfide with the chemical formula (Fe,Ni)9S8. Pentlandite has a narrow variation range in Ni:Fe but it is usually described as having a Ni:Fe of 1:1. It also contains minor cobalt, usually at low levels as a fraction of weight.

<span class="mw-page-title-main">Chalcopyrite</span> Copper iron sulfide mineral

Chalcopyrite ( KAL-kə-PY-ryte, -⁠koh-) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green-tinged black.

<span class="mw-page-title-main">Bornite</span> Sulfide mineral

Bornite, also known as peacock ore, is a sulfide mineral with chemical composition Cu5FeS4 that crystallizes in the orthorhombic system (pseudo-cubic).

<span class="mw-page-title-main">Covellite</span> Sulfide mineral

Covellite is a rare copper sulfide mineral with the formula CuS. This indigo blue mineral is commonly a secondary mineral in limited abundance and although it is not an important ore of copper itself, it is well known to mineral collectors.

<span class="mw-page-title-main">Sulfide mineral</span> Class of minerals containing sulfide or disulfide as the major anion

The sulfide minerals are a class of minerals containing sulfide (S2−) or disulfide (S22−) as the major anion. Some sulfide minerals are economically important as metal ores. The sulfide class also includes the selenides, the tellurides, the arsenides, the antimonides, the bismuthinides, the sulfarsenides and the sulfosalts. Sulfide minerals are inorganic compounds.

<span class="mw-page-title-main">Copper monosulfide</span> Chemical compound

Copper monosulfide is a chemical compound of copper and sulfur. It was initially thought to occur in nature as the dark indigo blue mineral covellite. However, it was later shown to be rather a cuprous compound, formula Cu+3S(S2). CuS is a moderate conductor of electricity. A black colloidal precipitate of CuS is formed when hydrogen sulfide, H2S, is bubbled through solutions of Cu(II) salts. It is one of a number of binary compounds of copper and sulfur (see copper sulfide for an overview of this subject), and has attracted interest because of its potential uses in catalysis and photovoltaics.

<span class="mw-page-title-main">Siegenite</span>

Siegenite (also called grimmite, or nickel cobalt sulfide) is a ternary transition metal dichalcogenide compound with the chemical formula (Ni,Co)3S4. It has been actively studied as a promising material system for electrodes in electrochemical energy applications due to its better conductivity, greater mechanical and thermal stability, and higher performance compared to metal oxides currently in use. Potential applications of this material system include supercapacitors, batteries, electrocatalysis, dye-sensitized solar cells, photocatalysis, glucose sensors, and microwave absorption.

<span class="mw-page-title-main">Greigite</span> Iron sulfide mineral of spinel structure

Greigite is an iron sulfide mineral with the chemical formula Fe2+Fe3+2S4. It is the sulfur equivalent of the iron oxide magnetite (Fe3O4). It was first described in 1964 for an occurrence in San Bernardino County, California, and named after the mineralogist and physical chemist Joseph W. Greig (1895–1977).

<span class="mw-page-title-main">Digenite</span> Copper sulfide mineral

Digenite is a copper sulfide mineral with formula: Cu9S5. Digenite is a black to dark blue opaque mineral that crystallizes with a trigonal - hexagonal scalenohedral structure. In habit it is usually massive, but does often show pseudo-cubic forms. It has poor to indistinct cleavage and a brittle fracture. It has a Mohs hardness of 2.5 to 3 and a specific gravity of 5.6. It is found in copper sulfide deposits of both primary and supergene occurrences. It is typically associated with and often intergrown with chalcocite, covellite, djurleite, bornite, chalcopyrite and pyrite. The type locality is Sangerhausen, Thuringia, Germany, in copper slate deposits.

<span class="mw-page-title-main">Djurleite</span> Copper sulfide mineral

Djurleite is a copper sulfide mineral of secondary origin with formula Cu31S16 that crystallizes with monoclinic-prismatic symmetry. It is typically massive in form, but does at times develop thin tabular to prismatic crystals. It occurs with other supergene minerals such as chalcocite, covellite and digenite in the enriched zone of copper orebodies. It is a member of the chalcocite group, and very similar to chalcocite, Cu2S, in its composition and properties, but the two minerals can be distinguished from each other by x-ray powder diffraction. Intergrowths and transformations between djurleite, digenite and chalcocite are common. Many of the reported associations of digenite and djurleite, however, identified by powder diffraction, could be anilite and djurleite, as anilite transforms to digenite during grinding.

<span class="mw-page-title-main">Polydymite</span>

Polydymite, Ni2+Ni23+S4, is a supergene thiospinel sulfide mineral associated with the weathering of primary pentlandite nickel sulfide.

<span class="mw-page-title-main">Penroseite</span>

Penroseite is a rare selenide mineral with formula (Ni,Co,Cu)Se2. It has a gray-steel color and black streak with a hardness of 3. It is an isometric mineral, 2/m3. Penroseite was first discovered in 1925 in a Bolivian rhyolite. It was named for Richard Penrose (1863–1931), an economic geologist.

Linnaeite is a cobalt sulfide mineral with the composition Co+2Co+32S4. It was discovered in 1845 in Västmanland, Sweden, and was named to honor Carl Linnaeus (1707–1778).

Copper sulfides describe a family of chemical compounds and minerals with the formula CuxSy. Both minerals and synthetic materials comprise these compounds. Some copper sulfides are economically important ores.

<span class="mw-page-title-main">Copper(I) sulfide</span> Chemical compound

Copper(I) sulfide is a copper sulfide, a chemical compound of copper and sulfur. It has the chemical compound Cu2S. It is found in nature as the mineral chalcocite. It has a narrow range of stoichiometry ranging from Cu1.997S to Cu2.000S. Samples are typically black.

<span class="mw-page-title-main">Cobalt sulfide</span> Chemical compound

Cobalt sulfide is the name for chemical compounds with a formula CoxSy. Well-characterized species include minerals with the formula CoS, CoS2, Co3S4, and Co9S8. In general, the sulfides of cobalt are black, semiconducting, insoluble in water, and nonstoichiometric.

Fletcherite is a rare thiospinel sulfide mineral with formula Cu(Ni,Co)2S4. It is an opaque metallic steel gray mineral which crystallizes in the cubic crystal system. It is a member of the linnaeite group.

The thiospinel group is a group of sulfide minerals with a general formula AB2X4 where A is nominally a +2 metal, B is a +3 metal and X is -2 sulfide or similar anion. Thio refers to sulfur and spinel indicates their isometric spinel-like structure.

<span class="mw-page-title-main">Kesterite</span>

Kësterite is a sulfide mineral with a chemical formula of Cu2(Zn,Fe)SnS4. In its lattice structure, zinc and iron atoms share the same lattice sites. Kesterite is the Zn-rich variety whereas the Zn-poor form is called ferrokesterite or stannite. Owing to their similarity, kesterite is sometimes called isostannite. The synthetic form of kesterite is abbreviated as CZTS. The name kesterite is sometimes extended to include this synthetic material and also CZTSe, which contains selenium instead of sulfur.

<span class="mw-page-title-main">Coupled substitution</span> Geological process by which two elements simultaneously substitute into a crystal

Coupled substitution is the geological process by which two elements simultaneous substitute into a crystal in order to maintain overall electrical neutrality and keep the charge constant. In forming a solid solution series, ionic size is more important than ionic charge, as this can be compensated for elsewhere in the structure.

References

  1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi: 10.1180/mgm.2021.43 . S2CID   235729616.
  2. 1 2 Ramdohr, R (1980) The Ore Minerals and their Intergrowths. Pergamom.
  3. Criddle, A J and Stanley, C J (1993) Quantitative data file for ore minerals. Chapman & Hall page 74
  4. Mineralienatlas
  5. "Carrollite Mineral Data".
  6. 1 2 3 http://www.mindat.org/min-911.html Mindat.org
  7. http://rruff.geo.arizona.edu/doclib/hom/carrollite.pdf Handbook of Mineralogy
  8. Gaines et al (1997) Dana's New Mineralogy Eighth Edition. Wiley
  9. Klein and Hurlbut (1993) Manual of Mineralogy, 21st edition
  10. Charnock, Garner, Pattrick and Vaughan (1990) American Mineralogist 75: 247-255
  11. Electronic environments in carrollite, CuCo2S4, determined by soft X-ray photoelectron and absorption spectroscopy.
    Buckley AN, Skinner WM, Harmer SL, Pring A, Fan LJ
    GEOCHIMICA ET COSMOCHIMICA ACTA Volume: 73 Issue: 15 Pages: 4452–4467
  12. Magnetism and Superconductivity in Copper Spinels
    Kazuo Miyatani, Toshiro Tanaka, Shigenobu Sakita1, Masayasu Ishikawa and Naoki Snirakawa, Jpn. J. Appl. Phys. 32 (1993) Supplement 32-3 pp. 448–450
  13. Wagner and Cook (1999) Canadian Mineralogist 37:545 - 558
  14. Clark, Alan H (1974) American Mineralogist 59: 302-306
  15. 1 2 Craig, J R, Vaughan, D J and Higgins, J B (1979) Economic Geology 74:657-671
  16. Currier, R H (2002) Mineralogical Record 33: 473-487