Cubanite is a copperironsulfide mineral that commonly occurs as a minor alteration mineral in magmaticsulfide 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.[2] Cubanite is chemically similar to chalcopyrite, however it is the less common copper iron sulfide mineral due to crystallization requirements.
Cubanite
Striated, cyclically-twinned cubanite crystals from the Chibougamau mines of Quebec. (size: 1.5 x 1.3 x 1.0 cm)
Cubanite occurs in high temperature hydrothermal mineral deposits with pyrrhotite and pentlandite as intergrowths with chalcopyrite.[4] It results from exsolution from chalcopyrite at temperatures below 200 to 210 °C.[4] If cubanite is exposed to temperatures above 210 °C, it will transform into isocubanite. After this transformation, if it begins to cool, it will not revert to cubanite.[5] Upon its transformation to isocubanite it will lose its highly magnetic property due to its change from an orthorhombic to a cubic crystal structure.[6] Cubanite has been identified on chondrites and within dust grain samples and has improved the precision of copper isotope analysis.
Iridescent and highly lustrous brass-yellow cubanite crystal from Chibougamau, Quebec (size: 1.7 x 1.0 x 0.7 cm)
Cubanite comes from the Spanish word Cubano, or Cuban in English, and the suffix -ite, when naming a mineral. Cubanite was first described in 1843 for its occurrence in the Mayarí-Baracoa Belt, HolguÍn Province, Cuba. It may also be referenced as barracanite in some literature.[2]
Association and alterationEdit
As a minor alteration mineral, cubanite can only form when there is hydrothermal alteration of magmatic ores. The ores that are associated with cubanite are unaltered pyrrhotite-pentlandite-chalcopyrite ores that experience alteration to millerite-pyrite-chalcopyrite-cubanite ores, like those seen in the Bushveld Complex.[7] For cubanite to form from chalcopyrite, a loss of copper relative to sulfur and iron and an increase in iron relative to sulfur must occur.[7] This significant change in mineralogy results crystal structure change from tetragonal chalcopyrite to orthorhombic cubanite. With an increase in temperature above 210 °C, alteration continues and cubanite will transform into isocubanite, an isometric polymorph. There will be no transformation back to cubanite upon the cooling of the isocubanite.[5]
Extraterrestrial cubaniteEdit
Tagish Lake Meteorite, Classified as CI-2 due to presence of chondrules
Although cubanite forms in hydrothermal mineral deposits, there are occurrences of cubanite that did not form on earth. Cubanite has been found in carbonaceous chondrite meteorites, specifically class CI-chondrites, as well as in cometary samples from NASA’s Stardust spacecraft.[8] Data from the Itokawa asteroid, collected by the Hayabusa spacecraft, indicated that a 2-micrometre grain of cubanite was found on the S-type asteroid. This is the first time cubanite has been found on another asteroid that was not class C-type. However, further inspection of the sample revealed that the cubanite likely formed exogeneous to the Itokawa body.[9]
Synthetic cubaniteEdit
Although synthetic and chondritic cubanite have structural variations, synthesis of cubanite still grants insight into the formation of CI-chondrites. Using a lab-based variant of hydrothermal recrystallization, temperatures between 150-200 °C, and a pH of 9, scientists were able to determine compositions needed to replicate CI-chondrite mineralogy. Experiments that began with copper + iron + sulfur, covellite + troilite, and copper + sulfur + troilite all formed cubanite. Starting with troilite instead of iron metal reinforces previous studies that sulfides on Cl-chondrites are the resultant of oxidation of troilite by hydrothermal processes.[8]
Copper isotope analysisEdit
Due to its complex growth nature, Cubanite has been the test subject for instrumental preference in copper isotope microanalysis. It was found that ultra violet laser ablation multiple collector inductively coupled plasma mass spectrometry (UV-fs-LA-MC-ICP-MS) improves precision in respect to copper isotopes, when compared to the use of near infrared (NIR-fs-LA-MC-ICP-MS) methods.[10]
^ abChandra, U.; Parthasarathy, G.; Sharma, P. (2010-10-01). "SYNTHETIC CUBANITE CuFe2S3: PRESSURE-INDUCED TRANSFORMATION TO ISOCUBANITE". The Canadian Mineralogist. 48 (5): 1137–1147. Bibcode:2010CaMin..48.1137C. doi:10.3749/canmin.48.5.1137. ISSN 0008-4476.
^Sawada, M.; Ozima, M.; Fujiki, Y. (1962). "Magnetic Properties of Cubanite (CuFe2S3)". Journal of Geomagnetism and Geoelectricity. 14 (2): 107–112. Bibcode:1962JGG....14..107S. doi:10.5636/jgg.14.107. ISSN 0022-1392.
^ abHolwell, David A.; Adeyemi, Zeinab; Ward, Laura A.; Smith, Daniel J.; Graham, Shaun D.; McDonald, Iain; Smith, Jennifer W. (December 2017). "Low temperature alteration of magmatic Ni-Cu-PGE sulfides as a source for hydrothermal Ni and PGE ores: A quantitative approach using automated mineralogy". Ore Geology Reviews. 91: 718–740. Bibcode:2017OGRv...91..718H. doi:10.1016/j.oregeorev.2017.08.025. ISSN 0169-1368.
^ abBerger, Eve L.; Keller, Lindsay P.; Lauretta, Dante S. (2015). "An experimental study of the formation of cubanite (CuFe2S3) in primitive meteorites". Meteoritics & Planetary Science. 50 (1): 1–14. Bibcode:2015M&PS...50....1B. doi:10.1111/maps.12399. ISSN 1945-5100. S2CID 95725179.
^Burgess, Katherine; Stroud, Rhonda (August 2020). "STEM of Three Itokawa Grains: Space Weathering and Presence of Cubanite". Microscopy and Microanalysis. 26 (S2): 2602–2604. Bibcode:2020MiMic..26S2602B. doi:10.1017/S1431927620022151. ISSN 1431-9276. S2CID 225397714.
^IKEHATA, Kei; HIRATA, Takafumi (2013). "Evaluation of UV-fs-LA-MC-ICP-MS for Precise in situ Copper Isotopic Microanalysis of Cubanite". Analytical Sciences. 29 (12): 1213–1217. doi:10.2116/analsci.29.1213. ISSN 0910-6340. PMID 24334990.
Wikimedia Commons has media related to Cubanite.
This article about a specific sulfide mineral is a stub. You can help Wikipedia by expanding it.
cubanite, copper, iron, sulfide, mineral, that, commonly, occurs, minor, alteration, mineral, magmatic, sulfide, deposits, chemical, formula, cufe2s3, when, found, bronze, brass, yellow, appearance, mohs, hardness, scale, cubanite, falls, between, orthorhombic. 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 2 Cubanite is chemically similar to chalcopyrite however it is the less common copper iron sulfide mineral due to crystallization requirements CubaniteStriated cyclically twinned cubanite crystals from the Chibougamau mines of Quebec size 1 5 x 1 3 x 1 0 cm GeneralCategorySulfide mineralFormula repeating unit CuFe2S3IMA symbolCbn 1 Strunz classification2 CB 55aCrystal systemOrthorhombicCrystal classDipyramidal mmm H M symbol 2 m 2 m 2 m Space groupPcmnUnit cella 6 467 1 A b 11 117 1 A c 6 231 2 A Z 4IdentificationColorBronze to brass yellowCrystal habitCrystals elongated to thick tabular striated also massiveTwinningCommon with twin plane 110 in pairs also as fourlings and pseudohexagonal sixlingsCleavageParting on 110 and 13 0 FractureConchoidalMohs scale hardness3 5 4LusterMetallicStreakBlackDiaphaneityOpaqueSpecific gravity4 0 4 2Optical propertiesDistinctly anisotropic on polished surfaceOther characteristicsStrongly magneticReferences 2 3 4 Cubanite occurs in high temperature hydrothermal mineral deposits with pyrrhotite and pentlandite as intergrowths with chalcopyrite 4 It results from exsolution from chalcopyrite at temperatures below 200 to 210 C 4 If cubanite is exposed to temperatures above 210 C it will transform into isocubanite After this transformation if it begins to cool it will not revert to cubanite 5 Upon its transformation to isocubanite it will lose its highly magnetic property due to its change from an orthorhombic to a cubic crystal structure 6 Cubanite has been identified on chondrites and within dust grain samples and has improved the precision of copper isotope analysis Contents 1 Etymology and history 2 Association and alteration 3 Extraterrestrial cubanite 3 1 Synthetic cubanite 4 Copper isotope analysis 5 ReferencesEtymology and history Edit nbsp Iridescent and highly lustrous brass yellow cubanite crystal from Chibougamau Quebec size 1 7 x 1 0 x 0 7 cm Cubanite comes from the Spanish word Cubano or Cuban in English and the suffix ite when naming a mineral Cubanite was first described in 1843 for its occurrence in the Mayari Baracoa Belt HolguIn Province Cuba It may also be referenced as barracanite in some literature 2 Association and alteration EditAs a minor alteration mineral cubanite can only form when there is hydrothermal alteration of magmatic ores The ores that are associated with cubanite are unaltered pyrrhotite pentlandite chalcopyrite ores that experience alteration to millerite pyrite chalcopyrite cubanite ores like those seen in the Bushveld Complex 7 For cubanite to form from chalcopyrite a loss of copper relative to sulfur and iron and an increase in iron relative to sulfur must occur 7 This significant change in mineralogy results crystal structure change from tetragonal chalcopyrite to orthorhombic cubanite With an increase in temperature above 210 C alteration continues and cubanite will transform into isocubanite an isometric polymorph There will be no transformation back to cubanite upon the cooling of the isocubanite 5 Extraterrestrial cubanite Edit nbsp Tagish Lake Meteorite Classified as CI 2 due to presence of chondrulesAlthough cubanite forms in hydrothermal mineral deposits there are occurrences of cubanite that did not form on earth Cubanite has been found in carbonaceous chondrite meteorites specifically class CI chondrites as well as in cometary samples from NASA s Stardust spacecraft 8 Data from the Itokawa asteroid collected by the Hayabusa spacecraft indicated that a 2 micrometre grain of cubanite was found on the S type asteroid This is the first time cubanite has been found on another asteroid that was not class C type However further inspection of the sample revealed that the cubanite likely formed exogeneous to the Itokawa body 9 Synthetic cubanite Edit Although synthetic and chondritic cubanite have structural variations synthesis of cubanite still grants insight into the formation of CI chondrites Using a lab based variant of hydrothermal recrystallization temperatures between 150 200 C and a pH of 9 scientists were able to determine compositions needed to replicate CI chondrite mineralogy Experiments that began with copper iron sulfur covellite troilite and copper sulfur troilite all formed cubanite Starting with troilite instead of iron metal reinforces previous studies that sulfides on Cl chondrites are the resultant of oxidation of troilite by hydrothermal processes 8 Copper isotope analysis EditDue to its complex growth nature Cubanite has been the test subject for instrumental preference in copper isotope microanalysis It was found that ultra violet laser ablation multiple collector inductively coupled plasma mass spectrometry UV fs LA MC ICP MS improves precision in respect to copper isotopes when compared to the use of near infrared NIR fs LA MC ICP MS methods 10 nbsp Inductively Coupled Plasma Mass Spectrometry ICP MS analytical instrumentReferences Edit 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 a b c Mindat org Webmineral a b c Handbook of Mineralogy a b Chandra U Parthasarathy G Sharma P 2010 10 01 SYNTHETIC CUBANITE CuFe2S3 PRESSURE INDUCED TRANSFORMATION TO ISOCUBANITE The Canadian Mineralogist 48 5 1137 1147 Bibcode 2010CaMin 48 1137C doi 10 3749 canmin 48 5 1137 ISSN 0008 4476 Sawada M Ozima M Fujiki Y 1962 Magnetic Properties of Cubanite CuFe2S3 Journal of Geomagnetism and Geoelectricity 14 2 107 112 Bibcode 1962JGG 14 107S doi 10 5636 jgg 14 107 ISSN 0022 1392 a b Holwell David A Adeyemi Zeinab Ward Laura A Smith Daniel J Graham Shaun D McDonald Iain Smith Jennifer W December 2017 Low temperature alteration of magmatic Ni Cu PGE sulfides as a source for hydrothermal Ni and PGE ores A quantitative approach using automated mineralogy Ore Geology Reviews 91 718 740 Bibcode 2017OGRv 91 718H doi 10 1016 j oregeorev 2017 08 025 ISSN 0169 1368 a b Berger Eve L Keller Lindsay P Lauretta Dante S 2015 An experimental study of the formation of cubanite CuFe2S3 in primitive meteorites Meteoritics amp Planetary Science 50 1 1 14 Bibcode 2015M amp PS 50 1B doi 10 1111 maps 12399 ISSN 1945 5100 S2CID 95725179 Burgess Katherine Stroud Rhonda August 2020 STEM of Three Itokawa Grains Space Weathering and Presence of Cubanite Microscopy and Microanalysis 26 S2 2602 2604 Bibcode 2020MiMic 26S2602B doi 10 1017 S1431927620022151 ISSN 1431 9276 S2CID 225397714 IKEHATA Kei HIRATA Takafumi 2013 Evaluation of UV fs LA MC ICP MS for Precise in situ Copper Isotopic Microanalysis of Cubanite Analytical Sciences 29 12 1213 1217 doi 10 2116 analsci 29 1213 ISSN 0910 6340 PMID 24334990 nbsp Wikimedia Commons has media related to Cubanite nbsp This article about a specific sulfide mineral is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Cubanite amp oldid 1170401282, wikipedia, wiki, book, books, library,
