Onyx is the parallel-banded variety of chalcedony, an oxide mineral. Agate and onyx are both varieties of layered chalcedony that differ only in the form of the bands; agate has curved bands while onyx has parallel bands. The colors of its bands range from black to almost every color. Specimens of onyx commonly contain bands of black and/or white.[1] Onyx, as a descriptive term, has also been applied to parallel-banded varieties of alabaster, marble, calcite, obsidian, and opal, and misleadingly to materials with contorted banding, such as "cave onyx" and "Mexican onyx".[1][3][4]
Onyx comes through Latin (of the same spelling), from the Ancient Greek ὄνυξ, meaning "claw" or "fingernail". Onyx with pink and white bands can sometimes resemble a fingernail.[5] The English word "nail" is cognate with the Greek word.
VarietiesEdit
Cabochons of red onyx, also called sardonyxBlack onyx with white streaks
Onyx is formed of bands of chalcedony in alternating colors. It is cryptocrystalline, consisting of fine intergrowths of the silica minerals quartz and moganite. Its bands are parallel to one another, as opposed to the more chaotic banding that often occurs in agates.[6]
Sardonyx is a variant in which the colored bands are sard (shades of red) rather than black. Black onyx is perhaps the most famous variety, but is not as common as onyx with colored bands. Artificial treatments have been used since ancient times to produce both the black color in "black onyx" and the reds and yellows in sardonyx. Most "black onyx" on the market is artificially colored.[7][8]
Imitations and treatmentsEdit
The name has also commonly been used to label other banded materials, such as banded calcite found in Mexico, India, and other places, and often carved, polished and sold. This material is much softer than true onyx, and much more readily available. The majority of carved items sold as "onyx" today are this carbonate material.[9][10]
Artificial onyx types have also been produced from common chalcedony and plain agates. The first-century naturalist Pliny the Elder described these techniques being used in Roman times.[11] Treatments for producing black and other colours include soaking or boiling chalcedony in sugar solutions, then treating with sulfuric or hydrochloric acid to carbonise sugars which had been absorbed into the top layers of the stone.[8][12] These techniques are still used, as well as other dyeing treatments, and most so-called "black onyx" sold is artificially treated.[13] In addition to dye treatments, heating and treatment with nitric acid have been used to lighten or eliminate undesirable colours.[8]
Geographic occurrenceEdit
Onyx is a gemstone found in various regions of the world including Greece, Yemen, Uruguay, Argentina, Australia, Brazil, Canada, China, Czech Republic, Germany, Pakistan, India, Indonesia, Madagascar, Latin America, the UK, and various states in the US.[9]
Historical useEdit
The Gemma Augustea is a Roman cameo produced 9–12 AD and carved in a two-layered onyx gem (19 × 23 cm)
It has a long history of use for hardstone carving and jewelry, where it is usually cut as a cabochon or into beads. It has also been used for intaglio and hardstone cameoengraved gems, where the bands make the image contrast with the ground.[14] Some onyx is natural but much of the material in commerce is produced by the staining of agate.[15]
Onyx was used in Egypt as early as the Second Dynasty to make bowls and other pottery items.[16] Use of sardonyx appears in the art of MinoanCrete, notably from the archaeological recoveries at Knossos.[17]
Brazilian green onyx was often used as plinths for art deco sculptures created in the 1920s and 1930s. The German sculptor Ferdinand Preiss used Brazilian green onyx for the base on the majority of his chryselephantine sculptures.[18] Green onyx was also used for trays and pin dishes – produced mainly in Austria – often with small bronze animals or figures attached.[19]
Onyx is mentioned in the Bible many times.[20] Sardonyx (onyx in which white layers alternate with sard - a brownish color) is mentioned in the Bible as well.[21]
The Throne of Jahangir (Urdu: Takht-i-Jahangir) was made of black onyx. It was built by Mughal emperor Jahangir (31 August 1569 – 28 October 1627) in 1602 and is located at the Diwan-i-Khas (hall of private audience) at the Red Fort in Agra, Uttar Pradesh, India.
SuperstitionsEdit
The ancient Romans entered battle carrying amulets of sardonyx engraved with Mars, the god of war. This was believed to bestow courage in battle. In Renaissance Europe, wearing sardonyx was believed to bestow eloquence.[25] A traditional Persian belief is that it helped with epilepsy.[26] Sardonyx was traditionally used by English midwives to ease childbirth by laying it between the breasts of the mother.[27]
^"Online Etymology Dictionary". etymonline.com. Retrieved 22 August 2015.
^Assaad, Fakhry A.; LaMoreaux, Philip E. Sr. (2004). Hughes, Travis H. (ed.). Field Methods for Geologists and Hydrogeologists. Berlin, Heidelberg, New York: Springer-Verlag. p. 8. ISBN3-540-40882-7.
^Hurlbut, Cornelius S.; Sharp, W. Edwin (1998). Dana's Minerals and How to Study Them (4th ed.). New York, New York: Wiley. p. 200. ISBN0-471-15677-9.
^ abO'Donoghue, Michael (1997). Synthetic, Imitation, and Treated Gemstones. Boston: Butterworth-Heinemann. pp. 125–127. ISBN0-7506-3173-2.
^Read, Peter G. (1999). Gemmology. Oxford: Butterworth-Heinemann. p. 160. ISBN0-7506-4411-7.
^Liddicoat, Richard Thomas (1987). Handbook of Gem Identification (12th ed.). Santa Monica, California: Gemological Institute of America. pp. 158–160. ISBN0-87311-012-9.
^Kraus, Edward Henry; Slawson, Chester Baker (1947). Gems and Gem Materials. New York, New York: McGraw-Hill. p. 227.
^Liddicoat, Richard Thomas; Copeland, Lawrence L. (1974). The Jewelers' Manual. Los Angeles, California: Gemological Institute of America. p. 87.
^Porter, Mary Winearls (1907). What Rome was Built with: A Description of the Stones Employed. Rome: H. Frowde. p. 108.
^C. Michael Hogan (2007) Knossos fieldnotes, The Modern Antiquarian
^"Ferdinand Preiss". Hickmet.com. Retrieved 18 June 2015.
^The Mining World, Volume 32, June 25, 1910, p.1267
^Three thousand years of mental healing By George Barton Cutten, 1911 P.202
External linksEdit
Wikimedia Commons has media related to Onyx.
Look up onyx in Wiktionary, the free dictionary.
Rudler, Frederick William (1911). "Onyx" . Encyclopædia Britannica. Vol. 20 (11th ed.). p. 118.
October 16, 2023
onyx, this, article, about, mineral, york, group, group, other, uses, disambiguation, parallel, banded, variety, chalcedony, oxide, mineral, agate, onyx, both, varieties, layered, chalcedony, that, differ, only, form, bands, agate, curved, bands, while, onyx, . This article is about the mineral For the New York hip hop group see Onyx hip hop group For other uses see Onyx disambiguation Onyx is the parallel banded variety of chalcedony an oxide mineral Agate and onyx are both varieties of layered chalcedony that differ only in the form of the bands agate has curved bands while onyx has parallel bands The colors of its bands range from black to almost every color Specimens of onyx commonly contain bands of black and or white 1 Onyx as a descriptive term has also been applied to parallel banded varieties of alabaster marble calcite obsidian and opal and misleadingly to materials with contorted banding such as cave onyx and Mexican onyx 1 3 4 OnyxGeneralCategoryChalcedony variety oxide minerals Formula repeating unit SiO2 silicon dioxide Crystal systemTrigonalIdentificationFormula mass60 g molColorVariousCleavageNoneFractureUneven conchoidalMohs scale hardness6 5 7LusterVitreous silkyStreakWhiteDiaphaneityTranslucentSpecific gravity2 55 2 70Optical propertiesUniaxial Refractive index1 530 1 543References 1 2 Contents 1 Etymology 2 Varieties 3 Imitations and treatments 4 Geographic occurrence 5 Historical use 5 1 Superstitions 6 See also 7 References 8 External linksEtymology EditOnyx comes through Latin of the same spelling from the Ancient Greek ὄny3 meaning claw or fingernail Onyx with pink and white bands can sometimes resemble a fingernail 5 The English word nail is cognate with the Greek word Varieties Edit nbsp Cabochons of red onyx also called sardonyx nbsp Black onyx with white streaksOnyx is formed of bands of chalcedony in alternating colors It is cryptocrystalline consisting of fine intergrowths of the silica minerals quartz and moganite Its bands are parallel to one another as opposed to the more chaotic banding that often occurs in agates 6 Sardonyx is a variant in which the colored bands are sard shades of red rather than black Black onyx is perhaps the most famous variety but is not as common as onyx with colored bands Artificial treatments have been used since ancient times to produce both the black color in black onyx and the reds and yellows in sardonyx Most black onyx on the market is artificially colored 7 8 Imitations and treatments EditThe name has also commonly been used to label other banded materials such as banded calcite found in Mexico India and other places and often carved polished and sold This material is much softer than true onyx and much more readily available The majority of carved items sold as onyx today are this carbonate material 9 10 Artificial onyx types have also been produced from common chalcedony and plain agates The first century naturalist Pliny the Elder described these techniques being used in Roman times 11 Treatments for producing black and other colours include soaking or boiling chalcedony in sugar solutions then treating with sulfuric or hydrochloric acid to carbonise sugars which had been absorbed into the top layers of the stone 8 12 These techniques are still used as well as other dyeing treatments and most so called black onyx sold is artificially treated 13 In addition to dye treatments heating and treatment with nitric acid have been used to lighten or eliminate undesirable colours 8 Geographic occurrence EditOnyx is a gemstone found in various regions of the world including Greece Yemen Uruguay Argentina Australia Brazil Canada China Czech Republic Germany Pakistan India Indonesia Madagascar Latin America the UK and various states in the US 9 Historical use Edit nbsp The Gemma Augustea is a Roman cameo produced 9 12 AD and carved in a two layered onyx gem 19 23 cm It has a long history of use for hardstone carving and jewelry where it is usually cut as a cabochon or into beads It has also been used for intaglio and hardstone cameo engraved gems where the bands make the image contrast with the ground 14 Some onyx is natural but much of the material in commerce is produced by the staining of agate 15 Onyx was used in Egypt as early as the Second Dynasty to make bowls and other pottery items 16 Use of sardonyx appears in the art of Minoan Crete notably from the archaeological recoveries at Knossos 17 Brazilian green onyx was often used as plinths for art deco sculptures created in the 1920s and 1930s The German sculptor Ferdinand Preiss used Brazilian green onyx for the base on the majority of his chryselephantine sculptures 18 Green onyx was also used for trays and pin dishes produced mainly in Austria often with small bronze animals or figures attached 19 Onyx is mentioned in the Bible many times 20 Sardonyx onyx in which white layers alternate with sard a brownish color is mentioned in the Bible as well 21 Onyx was known to the Ancient Greeks and Romans 22 The first century naturalist Pliny the Elder described both type of onyx and various artificial treatment techniques in his Naturalis Historia 11 Slabs of onyx from the Atlas Mountains were famously used by Mies van der Rohe in Villa Tugendhat at Brno completed 1930 to create a shimmering semi translucent interior wall 23 24 The Hotel de la Paiva in Paris is noted for its yellow onyx decor and the new Mariinsky Theatre Second Stage in St Petersburg uses yellow onyx in the lobby nbsp Throne of JahangirThe Throne of Jahangir Urdu Takht i Jahangir was made of black onyx It was built by Mughal emperor Jahangir 31 August 1569 28 October 1627 in 1602 and is located at the Diwan i Khas hall of private audience at the Red Fort in Agra Uttar Pradesh India Superstitions Edit The ancient Romans entered battle carrying amulets of sardonyx engraved with Mars the god of war This was believed to bestow courage in battle In Renaissance Europe wearing sardonyx was believed to bestow eloquence 25 A traditional Persian belief is that it helped with epilepsy 26 Sardonyx was traditionally used by English midwives to ease childbirth by laying it between the breasts of the mother 27 See also Edit nbsp Minerals portalBirthstone Gemstones representing a person s birth month Chalcedony Microcrystalline varieties of silica may contain moganite as well Gemstone Piece of mineral crystal used to make jewelry Jasper Chalcedony variety colored by iron oxide List of minerals List of minerals with Wikipedia articlesReferences Edit a b c Onyx Mindat org retrieved 2015 08 22 Onyx gemdat org Retrieved 2015 08 22 Manutchehr Danai Mohsen 2013 Dictionary of Gems and Gemology New York Springer pp 340 341 ISBN 9783662042885 Schumann Walter 2009 Gemstones of the World New York Sterling p 158 ISBN 9781402768293 Online Etymology Dictionary etymonline com Retrieved 22 August 2015 Assaad Fakhry A LaMoreaux Philip E Sr 2004 Hughes Travis H ed Field Methods for Geologists and Hydrogeologists Berlin Heidelberg New York Springer Verlag p 8 ISBN 3 540 40882 7 Sinkankas John 1959 Gemstones of North America Vol 1 Princeton New Jersey Van Nostrand p 316 a b c The Manufacture of Gem Stones Scientific American New York Munn amp Company 49 25 July 1874 a b Onyx mindat org Retrieved 22 August 2015 Hurlbut Cornelius S Sharp W Edwin 1998 Dana s Minerals and How to Study Them 4th ed New York New York Wiley p 200 ISBN 0 471 15677 9 a b O Donoghue Michael 1997 Synthetic Imitation and Treated Gemstones Boston Butterworth Heinemann pp 125 127 ISBN 0 7506 3173 2 Read Peter G 1999 Gemmology Oxford Butterworth Heinemann p 160 ISBN 0 7506 4411 7 Liddicoat Richard Thomas 1987 Handbook of Gem Identification 12th ed Santa Monica California Gemological Institute of America pp 158 160 ISBN 0 87311 012 9 Kraus Edward Henry Slawson Chester Baker 1947 Gems and Gem Materials New York New York McGraw Hill p 227 Liddicoat Richard Thomas Copeland Lawrence L 1974 The Jewelers Manual Los Angeles California Gemological Institute of America p 87 Porter Mary Winearls 1907 What Rome was Built with A Description of the Stones Employed Rome H Frowde p 108 C Michael Hogan 2007 Knossos fieldnotes The Modern Antiquarian Ferdinand Preiss Hickmet com Retrieved 18 June 2015 Lot 419 Schmidt Hofer Otto 1873 1925 Germany ArtValue com BibleGateway biblegateway com Retrieved 22 August 2015 BibleGateway biblegateway com Retrieved 22 August 2015 Administrator Onyx gemstone org Retrieved 22 August 2015 The Interiors Villa Tugendhat Retrieved 2 September 2017 Tugendhat Villa in Brno UNESCO Retrieved 2 September 2017 Firefly Guide to Gems By Cally Oldershaw p 168 The Mining World Volume 32 June 25 1910 p 1267 Three thousand years of mental healing By George Barton Cutten 1911 P 202External links Edit nbsp Wikimedia Commons has media related to Onyx nbsp Look up onyx in Wiktionary the free dictionary Rudler Frederick William 1911 Onyx Encyclopaedia Britannica Vol 20 11th ed p 118 Retrieved from https en wikipedia org w index php title Onyx amp oldid 1178646002, wikipedia, wiki, book, books, library,
