Atacamite

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Atacamite
Atacamite on malachite - Mt Gunson mines, South Australia.jpg
Atacamite from Mt. Gunson mines, South Australia
General
Category Halide mineral
Formula
(repeating unit)
Cu2Cl(OH)3
IMA symbol Ata [1]
Strunz classification 3.DA.10a
Crystal system Orthorhombic
Crystal class Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space group Pnma
Unit cell a = 6.03, b = 9.12
c = 6.865 [Å]; Z = 4
Identification
ColorBright green, dark emerald-green to blackish green
Crystal habit Slender prismatic crystals, fibrous, granular to compact, massive
Twinning Contact and penetration with complex twinned groupings
Cleavage Perfect on {010}, fair on {101}
Fracture Conchoidal
Tenacity Brittle
Mohs scale hardness3–3.5
Luster Adamantine to vitreous
Streak Apple green
Diaphaneity Transparent to translucent
Specific gravity 3.745–3.776
Optical propertiesBiaxial (−)
Refractive index nα = 1.831 nβ = 1.861 nγ = 1.880
Birefringence δ = 0.049
Pleochroism X = pale green; Y = yellow-green; Z = grass-green
2V angle Calculated: 74°
Dispersion r < v, strong
References [2] [3] [4] [5]

Atacamite is a copper halide mineral: a copper(II) chloride hydroxide with formula Cu2Cl(OH)3. It was first described for deposits in the Atacama Desert of Chile in 1802 by Dmitri de Gallitzin. [2] The Atacama Desert is also the namesake of the mineral.

Contents

Occurrence

Atacamite is polymorphous with botallackite, clinoatacamite, and paratacamite. [2] Atacamite is a comparatively rare mineral, formed from primary copper minerals in the oxidation or weathering zone of arid climates. It has also been reported as a volcanic sublimate from fumarole deposits, as sulfide alteration products in black smokers. [3] The mineral has also been found naturally on oxidized copper deposits in Chile, China, Russia, Czech Republic, Arizona, and Australia. [6] It occurs in association with cuprite, brochantite, linarite, caledonite, malachite, chrysocolla and its polymorphs. [3]

Synthetic Occurrence

Atacamite has been discovered in the patina of the Statue of Liberty, and as alteration of ancient bronze and copper artifacts. The mineral has been found as a pigment in sculpture, manuscripts, maps, and frescoes discovered in Eurasia, Russia, and Persia. [6]

Biomineral

Atacamite occurs as a biomineral in the jaws of bloodworms. [7] [8]

Related Research Articles

<i>Glycera</i> (annelid) Genus of annelid worms

The genus Glycera is a group of polychaetes commonly known as bloodworms. They are typically found on the bottom of shallow marine waters, and some species can grow up to 35 cm (14 in) in length.

<span class="mw-page-title-main">Niter</span> Mineral form of potassium nitrate

Niter or nitre is the mineral form of potassium nitrate, KNO3. It is a soft, white, highly soluble mineral found primarily in arid climates or cave deposits.

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

Chalcocite, copper(I) sulfide (Cu2S), is an important copper ore mineral. It is opaque and dark gray to black, with a metallic luster. It has a hardness of 2.5–3 on the Mohs scale. It is a sulfide with a monoclinic crystal system.

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

Cuprite is an oxide mineral composed of copper(I) oxide Cu2O, and is a minor ore of copper.

<span class="mw-page-title-main">Adamite</span> Zinc arsenate hydroxide mineral

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 a recently discovered mineral being an intermediate mineral with formula CuZn(AsO4)(OH). Manganese, cobalt, and nickel also substitute in the structure. An analogous zinc phosphate, tarbuttite, is known.

<span class="mw-page-title-main">Biomineralization</span> Process by which living organisms produce minerals

Biomineralization, also written biomineralisation, is the process by which living organisms produce minerals, often resulting in hardened or stiffened mineralized tissues. It is an extremely widespread phenomenon: all six taxonomic kingdoms contain members that are able to form minerals, and over 60 different minerals have been identified in organisms. Examples include silicates in algae and diatoms, carbonates in invertebrates, and calcium phosphates and carbonates in vertebrates. These minerals often form structural features such as sea shells and the bone in mammals and birds.

<span class="mw-page-title-main">Chlorargyrite</span> Mineral form of silver chloride

Chlorargyrite is the mineral form of silver chloride (AgCl). Chlorargyrite occurs as a secondary mineral phase in the oxidation of silver mineral deposits. It crystallizes in the isometric–hexoctahedral crystal class. Typically massive to columnar in occurrence it also has been found as colorless to variably yellow cubic crystals. The color changes to brown or purple on exposure to light. It is quite soft with a Mohs hardness of 1 to 2 and dense with a specific gravity of 5.55. It is also known as cerargyrite and, when weathered by desert air, as horn silver. Bromian chlorargyrite is also common. Chlorargyrite is water-insoluble.

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

Arthurite is a mineral composed of divalent copper and iron ions in combination with trivalent arsenate, phosphate and sulfate ions with hydrogen and oxygen. Initially discovered by Sir Arthur Russell in 1954 at Hingston Down Consols mine in Calstock, Cornwall, England, arthurite is formed as a resultant mineral in the oxidation region of some copper deposits by the variation of enargite or arsenopyrite. The chemical formula of Arthurite is CuFe23+(AsO4,PO4,SO4)2(O,OH)2·4H2O.

<span class="mw-page-title-main">Botallackite</span> Halide mineral

Botallackite, chemical formula Cu2(OH)3Cl is a secondary copper mineral, named for its type locality at the Botallack Mine, St Just in Penwith, Cornwall. It is polymorphous with atacamite, paratacamite and clinoatacamite.

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

Cubanite is a copper iron sulfide mineral that commonly occurs as a minor alteration mineral in magmatic sulfide deposits. It has the chemical formula CuFe2S3 and when found, it has a bronze to brass-yellow appearance. On the Mohs hardness scale, cubanite falls between 3.5 and 4 and has a orthorhombic crystal system. Cubanite is chemically similar to chalcopyrite; however, it is the less common copper iron sulfide mineral due to crystallization requirements.

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

Boleite is a complex halide mineral with formula: KPb26Ag9Cu24(OH)48Cl62. It was first described in 1891 as an oxychloride mineral. It is an isometric mineral which forms in deep-blue cubes. There are numerous minerals related to boleite, such as pseudoboleite, cumengite, and diaboleite, and these all have the same complex crystal structure. They all contain bright-blue cubic forms and are formed in altered zones of lead and copper deposits, produced during the reaction of chloride bearing solutions with primary sulfide minerals.

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

Calumetite is a natural rarely occurring mineral. It was discovered in 1963 at the Centennial Mine near Calumet, Michigan, United States. Calumetite was first discovered along with anthonyite. It has a chemical formula of Cu(OH,Cl)
2
•2(H
2
O)
.

<span class="mw-page-title-main">Dicopper chloride trihydroxide</span> Chemical compound

Dicopper chloride trihydroxide is the chemical compound with the formula Cu2(OH)3Cl. It is often referred to as tribasic copper chloride (TBCC), copper trihydroxyl chloride or copper hydroxychloride. It is a greenish crystalline solid encountered in mineral deposits, metal corrosion products, industrial products, art and archeological objects, and some living systems. It was originally manufactured on an industrial scale as a precipitated material used as either a chemical intermediate or a fungicide. Since 1994, a purified, crystallized product has been produced at the scale of thousands of tons per year, and used extensively as a nutritional supplement for animals.

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

Leightonite is a rare sulfate mineral with formula of K2Ca2Cu(SO4)4•2H2O.

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

Kröhnkite ( Na2Cu(SO4)2•2H2O ) is a rare copper sulfate mineral named after B. Kröhnke who first researched it. Kröhnkite may be replaced by Saranchinaite, the anhydrous form of the mineral, if heated to temperatures above 200 °C (392 °F).

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

Diaboleite is a blue-colored mineral with formula Pb2CuCl2(OH)4. It was discovered in England in 1923 and named diaboleite, from the Greek word διά and boleite, meaning "distinct from boleite". The mineral has since been found in a number of countries.

<span class="mw-page-title-main">Chloride-bearing deposits on Mars</span>

Across the southern highlands of Mars, approximately 640 sites of chloride-bearing deposits have been identified using the Thermal Emission Imaging System (THEMIS). These isolated, irregularly shaped patches have been dated to the older geologic periods on Mars: Noachian and Hesperian periods. On Earth, chlorides are known to form through aqueous processes. Similar processes are expected to be responsible for the formation of chloride deposits on Mars. The finding of these deposits is significant in that it provides further evidence for the presence of surface or subsurface water in ancient Mars.

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

Ammineite is the first recognized mineral containing ammine groups. Its formula is [CuCl2(NH3)2]. The mineral is chemically pure. It was found in a guano deposit in Chile. At the same site other ammine-containing minerals were later found:

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

Chalconatronite is a carbonate mineral and rare secondary copper mineral that contains copper, sodium, carbon, oxygen, and hydrogen, its chemical formula is Na2Cu(CO3)2•3(H2O). Chalconatronite is partially soluble in water, and only decomposes, although chalconatronite is soluble while cold, in dilute acids. The name comes from the mineral's compounds, copper ("chalcos" in Greek) and natron, naturally forming sodium carbonate. The mineral is thought to be formed by water carrying alkali carbonates (possibly from soil) reacting with bronze. Similar minerals include malachite, azurite, and other copper carbonates. Chalconatronite has also been found and recorded in Australia, Germany, and Colorado.

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

Paratacamite is a mineral in the halide minerals category. Its chemical formula is Cu3(Cu,Zn)(OH)6Cl2. Its name is derived from its association with atacamite.

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 3 Atacamite on Mindat.org
  3. 1 2 3 Handbook of Mineralogy
  4. Atacamite on Webmineral
  5. Mineralienatlas
  6. 1 2 "Atacamite – CAMEO". cameo.mfa.org. Retrieved 2017-10-15.
  7. Lichtenegger HC, Schöberl T, Bartl MH, Waite H, Stucky GD (October 2002). "High abrasion resistance with sparse mineralization: copper biomineral in worm jaws". Science. 298 (5592): 389–92. Bibcode:2002Sci...298..389L. doi:10.1126/science.1075433. PMID   12376695. S2CID   14001250.
  8. Lichtenegger HC, Schöberl T, Ruokolainen JT, et al. (August 2003). "Zinc and mechanical prowess in the jaws of Nereis, a marine worm". Proc. Natl. Acad. Sci. U.S.A. 100 (16): 9144–9. Bibcode:2003PNAS..100.9144L. doi: 10.1073/pnas.1632658100 . PMC   170886 . PMID   12886017.