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{{short description|Type of crucible steel}}
{{more citations needed|date=October 2021}}
{{Use dmy dates|date=August 2019}}
[[File:Watered pattern on sword blade1.Iran.JPG|thumb|upright=1.2|[[Crucible steel]]s like wootz steel and [[Damascus steel]] exhibit unique banding patterns because of the intermixed ferrite and cementite alloys in the steel.]]
'''Wootz steel''', also known as '''Seric steel''', is a [[crucible steel]] characterized by a pattern of bands and high carbon content. These bands are formed by sheets of microscopic [[carbide]]s within a tempered [[martensite]] or [[pearlite]] matrix in higher [[carbon steel]], or by [[Allotropes of iron|ferrite]] and pearlite banding in lower carbon steels. It was a pioneering [[steel alloy]] developed in [[southern India]] in the mid-1st millennium BC and exported globally.<ref name=":0">{{Cite journal|last=J.‐S. Park K. Rajan R. Ramesh|title=High‐carbon steel and ancient sword‐making as observed in a double‐edged sword from an Iron Age megalithic burial in Tamil Nadu, India|journal=Archaeometry|year=2020|volume=62|pages=68–80|doi=10.1111/arcm.12503|doi-access=free}}</ref>

==History==

Wootz steel originated in the mid-1st millennium BC in South India, in present-day [[Tiruchirappalli]], [[Kodumanal]], [[Erode]], [[Tamil Nadu]].<ref name=":0" /> There are several ancient Tamil, North Indian, Greek, Chinese and Roman literary references to high carbon Tamil steel.{{citation needed|date=June 2021}} In later times{{when|date=June 2021}}, wootz steel was also made in [[Golconda]] in [[Telangana]], [[Karnataka]] and Sri Lanka.<ref>{{cite journal |first=Sharada |last=Srinivasan |date=15 November 1994 |title=Wootz crucible steel: a newly discovered production site in South India |journal=Papers from the Institute of Archaeology |volume=5 |pages=49–59 |doi=10.5334/pia.60|doi-access=free }}</ref><ref>{{Cite journal |last1=Wijepala |first1=W. M. T. B. |last2=Young |first2=Sansfica M. |last3=Ishiga |first3=Hiroaki |date=2022-04-01 |title=Reading the archaeometallurgical findings of Yodhawewa site, Sri Lanka: contextualizing with South Asian metal history |url=https://doi.org/10.1007/s41826-022-00046-0 |journal=Asian Archaeology |language=en |volume=5 |issue=1 |pages=21–39 |doi=10.1007/s41826-022-00046-0 |s2cid=247355036 |issn=2520-8101}}</ref><ref>{{cite book |first=Herbert Henery |last=Coghlan |year=1977 |title=Notes on prehistoric and early iron in the Old World |pages=99–100 |edition=2nd |publisher=[[Pitt Rivers Museum]]}}</ref><ref>{{cite journal |first=B. |last=Sasisekharan |year=1999 |url=http://www.new1.dli.ernet.in/data1/upload/insa/INSA_1/20005b66_263.pdf |title=Technology of Iron and Steel in Kodumanal |journal=[[Indian Journal of History of Science]] |volume=34 |number=4 |archive-url=https://web.archive.org/web/20150724033115/http://www.new1.dli.ernet.in/data1/upload/insa/INSA_1/20005b66_263.pdf |archive-date=24 July 2015}}</ref> The steel was exported as cakes of steely iron that came to be known as "Wootz".<ref name="Davidson20">{{cite book |last=Davidson |first=Hilda Roderick Ellis |title=The Sword in Anglo-Saxon England: Its Archaeology and Literature |url=https://books.google.com/books?id=nY0T9n4zAQAC&pg=PA20 |date=1998 |publisher=Boydell & Brewer |isbn=978-0-85115-716-0 |page=20}}</ref>

The method was to heat black [[magnetite]] ore in the presence of carbon in a sealed clay crucible inside a charcoal furnace to completely remove [[slag]]. An alternative was to smelt the ore first to give [[wrought iron]], then heat and hammer it to remove slag. The carbon source was bamboo and leaves from plants such as [[Senna auriculata|Avārai]].<ref name="Davidson20"/><ref name="Burton111">{{cite book |last=Burton |first=Sir Richard Francis |author-link=Richard Francis Burton |title=The Book of the Sword |year=1884 |publisher=Chatto & Windus |location=London |page=111 |url=https://archive.org/stream/booksword00unkngoog#page/n152/mode/2up}}</ref> The Chinese and locals in Sri Lanka adopted the production methods of creating wootz steel from the Chera Tamils by the 5th century BC.<ref name="Needham282">{{cite book |title=Science and Civilisation in China: Volume 4, Physics and Physical Technology |date=1 April 1971 |first=Joseph |last=Needham |author-link=Joseph Needham |page=282 |publisher=Cambridge University Press |isbn=978-0-52107-060-7}}</ref><ref name="Manning365">{{cite book |last=Manning |first=Charlotte Speir |title=Ancient and Medieval India |volume=2 |url=https://books.google.com/books?id=nmESJR3a0RYC&pg=PA365 |isbn=978-0-543-92943-3 |page=365}}</ref> In Sri Lanka, this early steel-making method employed a unique wind furnace, driven by the monsoon winds. Production sites from antiquity have emerged, in places such as [[Anuradhapura]], [[Tissamaharama]] and [[Samanalawewa]], as well as imported artifacts of ancient iron and steel from Kodumanal. Recent archaeological excavations (2018) of the Yodhawewa site (in [[Mannar District|Mannar]] District) discovered a lower half-spherical furnace, crucible fragments, and lid fragments related to the crucible steel production through the carburization process.<ref>{{Cite journal |last1=Wijepala |first1=W. M. T. B. |last2=Young |first2=Sansfica M. |last3=Ishiga |first3=Hiroaki |date=2022-04-01 |title=Reading the archaeometallurgical findings of Yodhawewa site, Sri Lanka: contextualizing with South Asian metal history |url=https://doi.org/10.1007/s41826-022-00046-0 |journal=Asian Archaeology |language=en |volume=5 |issue=1 |pages=21–39 |doi=10.1007/s41826-022-00046-0 |s2cid=247355036 |issn=2520-8101}}</ref> A [[Tissamaharama Tamil Brahmi inscription|200 BC Tamil trade guild in Tissamaharama]], in the South East of Sri Lanka, brought with them some of the oldest iron and steel artifacts and production processes to the island from the [[classical antiquity|classical period]].<ref>''Hobbies'' (April 1963) Vol. 68, No.5, p.45, Chicago: Lightner Publishing Company.</ref><ref name="Mahathevan">{{cite news |url=http://www.thehindu.com/opinion/op-ed/An-epigraphic-perspective-on-the-antiquity-of-Tamil/article16265606.ece |title=An epigraphic perspective on the antiquity of Tamil |last=Mahathevan |first=Iravatham |date=24 June 2010 |newspaper=[[The Hindu]] |publisher=The Hindu Group |access-date=31 October 2010}}</ref><ref name="Ragupathy">{{cite news |url=http://www.tamilnet.com/art.html?catid=79&artid=32303 |title=Tissamaharama potsherd evidences ordinary early Tamils among population |last=Ragupathy |first=P. |date=28 June 2010 |work=Tamilnet |access-date=31 October 2010}}</ref><ref>{{cite journal |url=http://www.archaeology.lk/wp-content/uploads/2011/02/Dinithi-Volume-1-Issue-4.pdf |date=February 2012 |title=Dinithi |volume=1 |issue=4 |journal=Sri Lanka Archaeology }}{{Dead link|date=November 2018 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

Trade between South India and Sri Lanka through the [[Arabian Sea]] introduced wootz steel to Arabia. The term ''muhannad'' مهند or ''hendeyy'' هندي in pre-Islamic and early Islamic Arabic refers to sword blades made from Indian steel, which were highly prized, and are attested in [[Arabic poetry]]. Further trade spread the technology to the city of [[Damascus]], where an industry developed for making weapons of this steel. This led to the development of [[Damascus steel]]. The 12th century Arab traveler [[Muhammad al-Idrisi|Edrisi]] mentioned the "Hinduwani" or Indian steel as the best in the world.<ref name="SR_IISc">{{cite journal |first1=Sharada |last1=Srinivasan |first2=Srinivasa |last2=Ranganathan |title=India's Legendary Wootz Steel: An Advanced Material of the Ancient World |url=http://materials.iisc.ernet.in/~wootz/heritage/WOOTZ.htm |year=2004 |journal=[[Iron & Steel Heritage of India]] |pages=69–82 |oclc=82439861}}</ref> Arab accounts also point to the fame of 'Teling' steel, which can be taken to refer to the region of [[Telangana]]. The [[Golkonda|Golconda]] region of Telangana clearly being the nodal centre for the export of wootz steel to West Asia.<ref name="SR_IISc"/>

Another sign of its reputation is seen in a Persian phrase{{spaced ndash}}to give an "Indian answer", meaning "a cut with an Indian sword".<ref name="Manning365"/> Wootz steel was widely exported and traded throughout ancient [[Europe]] and the [[Arab world]], and became particularly famous in the [[Middle East]].<ref name="Manning365"/>

[[File:Wootz Steel Detail.jpg|thumb|upright|Detail of 17th–18th C. Indian tulwar/shamshir]]

=== Development of modern metallurgy ===

From the 17th century onwards, several European travelers observed the steel manufacturing in South India, at [[Mysore]], [[Malabar region|Malabar]] and [[Golconda]]. The word "wootz" appears to have originated as a mistranscription of ''wook''; the [[Tamil language]] root word for the alloy is ''urukku''.<ref name="GirijaJan2002">{{cite book|url=https://books.google.com/books?id=n4vtAAAAMAAJ|title=Tradition and innovation in the history of iron making: an Indo-European perspective|last1=Pande|first1=Girija|last2=af Geijerstam|first2=Jan|publisher=Pahar Parikarma|year=2002|isbn=978-81-86246-19-1|page=45}}</ref> Another{{Which|date=November 2021}}theory says that the word is a variation of ''uchcha'' or ''ucha''{{dubious|date=November 2021}} ("superior"). According to one theory, the word ''ukku'' is based on the meaning "melt, dissolve". Other [[Dravidian languages]] have similar-sounding words for steel: ''ukku'' in [[Kannada language|Kannada]]<ref name="RoddamSrini2003">{{cite book|url=https://books.google.com/books?id=XpFxcweodqQC&pg=PA135|title=The Dynamics of Technology: Creation and Diffusion of Skills and Knowledge|last1=Narasimha|first1=Roddam|last2=Srinivasan|first2=J.|last3=Biswas|first3=S. K.|date=2003|publisher=SAGE Publications|isbn=978-0-7619-9670-5|page=135}}</ref><ref>[[Michael Faraday]], as quoted by {{cite book|title=The Philosopher's Tree|last=Day|first=Peter|date=1999-01-01|publisher=Institute of Physics Publishing|isbn=978-0-7503-0571-6|location=Bristol, UK|page=108}}</ref> and [[Telugu language|Telugu]], and ''urukku'' in [[Malayalam]]. When [[Benjamin Heyne]] inspected the Indian steel in [[Ceded Districts]] and other Kannada-speaking areas, he was informed that the steel was ''ucha kabbina'' ("superior iron"), also known as ''ukku tundu'' in Mysore.<ref name="Edward1885">{{cite book |first=Edward |last=Balfour |title=The Cyclopædia of India and of Eastern and Southern Asia, Commercial Industrial, and Scientific: Products of the Mineral, Vegetable, and Animal Kingdoms, Useful Arts and Manufactures |url=https://archive.org/details/cyclopindiaeast03balfuoft |year=1885 |publisher=Bernard Quaritch |page=[https://archive.org/details/cyclopindiaeast03balfuoft/page/1092 1092]}}</ref><ref name="Jeans1880">{{cite book |first=James Stephen |last=Jeans |title=Steel: Its History, Manufacture, Properties and Uses |url=https://books.google.com/books?id=tOZZAAAAYAAJ&pg=PA294 |year=1880 |publisher=E. & F.N. Spon |page=294}}</ref>

Legends of wootz steel and Damascus swords aroused the curiosity of the European scientific community from the 17th to the 19th century. The use of high-[[carbon]] [[alloy]]s was little known in Europe<ref>{{cite journal |first1=Evelyne |last1=Godfrey |first2=Matthijs |last2=van Nie |title=A Germanic ultrahigh carbon steel punch of the Late Roman-Iron Age |journal=Journal of Archaeological Science |volume=31 |issue=8 |pages=1117–25 |year=2004 |doi=10.1016/j.jas.2004.02.002 |url=https://www.isis.stfc.ac.uk/Pages/a-germanic-ultrahigh-carbon-steel-punch-of-the-late-roman-iron-age.pdf}}
*{{cite news |author=Paul Rincon |date=12 May 2004 |title=Iron Age tool marks move to steel |work=BBC News |url=http://news.bbc.co.uk/2/hi/science/nature/3705205.stm}}</ref> previously and thus the research into wootz steel played an important role in the development of modern English, French and Russian [[metallurgy]].<ref name="Smith2012">{{cite book |first=Cyril Stanley |last=Smith |title=A History of Metallography: The Development of Ideas on the Structure of Metals Before 1890 |url=https://books.google.com/books?id=qMCKMQEACAAJ |date=2012 |publisher=Literary Licensing |isbn=978-1-258-47336-5}}</ref>

In 1790, samples of wootz steel were received by Sir [[Joseph Banks]], president of the British [[Royal Society]], sent by [[Helenus Scott]]. These samples were subjected to scientific examination and analysis by several experts.<ref>{{cite journal |last1=Pearson |first1=George |author-link=George Pearson (doctor) |title=Experiments and Observations to Investigate the Nature of a Kind of Steel, Manufactured at Bombay, and There Called Wootz: With Remarks on the Properties and Composition of the Different States of Iron |journal=[[Philosophical Transactions of the Royal Society of London]] |publisher=[[Royal Society of London]]|date=1 January 1795 |volume=85 |pages=322–346 |doi=10.1098/rstl.1795.0020 |jstor=106960|doi-access=free }}</ref><ref>{{cite journal |last1=Mushet |first1=D. |author-link=David Mushet |title=Experiments on Wootz |journal=Philosophical Transactions of the Royal Society of London |date=1 January 1805 |volume=95 |pages=163–175 |doi=10.1098/rstl.1805.0010 |jstor=107164|s2cid=115267901 }}</ref><ref>{{cite journal |first=Robert |last=Hadfield |author-link=Robert Hadfield |title=A Research on Faraday's "Steel and Alloys |journal=Philosophical Transactions of the Royal Society of London |volume=230 |issue=681–693 |year=1932 |pages=221–292 |doi=10.1098/rsta.1932.0007 |jstor=91231|bibcode=1932RSPTA.230..221H |doi-access=free }}</ref>

Specimens of daggers and other weapons were sent by the Rajas of India to [[the Great Exhibition]] in London in 1851 and [[1862 International Exhibition]]. Though the arms of the swords were beautifully decorated and jeweled, they were most highly prized for the quality of their steel. The swords of the Sikhs were said to bear bending and crumpling, and yet be fine and sharp.<ref name="Manning365"/>

==Characteristics==
Wootz is characterized by a pattern caused by bands of clustered {{chem|Fe|3|C}} particles made by melting of low levels of carbide-forming elements.<ref>{{harvnb|Verhoeven|Pendray|Dauksch |1998}}</ref> Wootz contains greater carbonaceous matter than common qualities of cast steel.{{citation needed|date=March 2020}}

The distinct patterns of Wootz steel that can be made through forging are wave, ladder, and rose patterns with finely spaced bonds. However, with hammering, dyeing, and [[etching]] further customized patterns were made.<ref>{{Cite book|last=Durand-Charre|first=Madeleine|url=https://books.google.com/books?id=n9pRE-4W8XIC&q=wootz&pg=PA21|title=Microstructure of Steels and Cast Irons|date=2004 |publisher=Springer |isbn=978-3-540-20963-8 }}</ref>

The presence of [[cementite]] [[nanowires]], and carbon nanotubes has been identified by Peter Pepler of [[TU Dresden]] in the microstructure of wootz steel.<ref>{{cite journal |url=http://www.nature.com/news/2006/061113/full/news061113-11.html |title=Sharpest cut from nanotube sword |first=Katharine |last=Sanderson |date=15 November 2006 |journal=[[Nature (journal)|Nature]] |doi=10.1038/news061113-11|s2cid=136774602 |doi-access=free }}</ref> There is a possibility of an abundance of ultrahard metallic carbides in the steel matrix precipitating out in bands.{{citation needed|date=April 2020}} Wootz swords were renowned for their sharpness and [[toughness]].{{citation needed|date=March 2020}}

=== Composition ===
T. H. Henry analyzed and recorded the composition of wootz steel samples provided by the [[Royal School of Mines]]. Recording:

[[Carbon]] (Combined) 1.34%

Carbon (Uncombined) 0.31%

[[Sulfur]] 0.17%

[[Silicon]] 0.04%

[[Arsenic]] 0.03%

Wootz steel was analyzed by Faraday and recorded to contain 0.01-0.07% [[aluminium]]. Faraday, Messrs (et al.), and Stodart hypothesized that aluminium was needed in the steel and was important in forming the excellent properties of wootz steel. However T. H. Henry deduced that presence of aluminium in the Wootz used by these studies was due to [[slag]], forming as silicates. Percy later reiterated that the quality of wootz steel does not depend on the presence of aluminium.<ref>{{Cite book|last=Percy|first=John|url=https://archive.org/details/metallurgyartex02percgoog|page=[https://archive.org/details/metallurgyartex02percgoog/page/n204 183]|title=Metallurgy: The Art of Extracting Metals from Their Ores, and Adapting Them to Various Purposes of Manufacture|date=1864|publisher=J. Murray|language=en}}</ref>

==Reproduction research==

Wootz steel has been reproduced and studied in depth by the Royal School of Mines.<ref>{{Cite book|last=Ure|first=Andrew|url=https://archive.org/details/adictionarychem00nichgoog|page=[https://archive.org/details/adictionarychem00nichgoog/page/n381 45]|title=A Dictionary of Chemistry: On the Basis of Mr. Nicholson's, in which the Principles of the Science are Investigated Anew and Its Applications to the Phenomena of Nature, Medicine, Mineralogy, Agriculture, and Manufactures Detailed|date=1821|publisher=Robert Desilver|language=en}}</ref> Dr. Pearson was the first to chemically examine wootz in 1795 and he published his contributions to the Philosophical Transactions of the Royal Society.<ref>{{Cite book|last=Neogi|first=Panchanan|url=https://archive.org/details/in.gov.ignca.9512|title=Iron in ancient India|date=1914|publisher=Indian Association for the Cultivation of Science|language=en}}</ref>

Russian metallurgist [[Pavel Petrovich Anosov]] (see [[Bulat steel]]) was almost able to reproduce ancient Wootz steel with nearly all of its properties and the steel he created was very similar to traditional Wootz. He documented four different methods of producing Wootz steel that exhibited traditional patterns. He died before he could fully document and publish his research. Oleg Sherby and Jeff Wadsworth and [[Lawrence Livermore National Laboratory]] have all done research, attempting to create steels with characteristics similar to Wootz, but without success. J.D Verhoeven and Alfred Pendray reconstructed methods of production, proved the role of impurities of ore in the pattern creation, and reproduced Wootz steel with patterns microscopically and visually identical to one of the ancient blade patterns. Reibold et al.'s analyses spoke of the presence of carbon nanotubes enclosing nanowires of cementite, with the trace elements/impurities of [[vanadium]], [[molybdenum]], [[chromium]] etc. contributing to their creation, in cycles of heating/cooling/forging. This resulted in a hard high carbon steel that remained malleable<ref>{{cite book |title=Discovery of Nanotubes in Ancient Damascus Steel |journal=Physics and Engineering of New Materials |volume=127 |pages=305–310 |date= 2009 |doi=10.1007/978-3-540-88201-5_35 | last1 = Reibold | first1 = Marianne | last2 = Paufler | first2 = Peter | last3 = Levin | first3 = Aleksandr A. | last4 = Kochmann | first4 = Werner | last5 = Pätzke | first5 = Nora | last6 = Meyer | first6 = Dirk C.|series=Springer Proceedings in Physics |publisher=[[Springer Science+Business Media|Springer]] |bibcode=2009penm.book..305R |isbn=978-3-540-88200-8 }}</ref>

There are smiths who are now consistently producing Wootz steel blades visually identical to the old patterns.<ref>{{cite journal |first1=Oleg |last1=Sherby |first2=Jeffrey |last2=Wadsworth |title=Ancient blacksmiths, the Iron Age, Damascus steels, and modem metallurgy |url=https://www.researchgate.net/figure/222563386_fig2_Fig-7-Two-Damascus-swords-and-surface-markings |journal=Journal of Materials Processing Technology |volume=117 |number=3 |pages=347–353 |date=23 November 2001 |doi=10.1016/S0924-0136(01)00794-4}}</ref> Steel manufactured in [[Kutch district|Kutch]] particularly enjoyed a widespread reputation, similar to those manufactured at [[Glasgow]] and [[Sheffield]].<ref name="Manning365" />

Wootz was made over nearly a 2,000-year period (the oldest sword samples date to around 200 AD) and the methods of production of ingots, the ingredients, and the methods of forging varied from one area to the next. Some Wootz blades displayed a pattern, while some did not. Heat treating was quite different from forging, and there were many different patterns which were created by the various smiths who spanned from China to Scandinavia.{{citation needed|date=March 2020}}

==See also==
*[[Toledo steel]]
*[[Damascus steel]]
*[[Noric steel]]
*[[Bulat steel]]
*[[Tamahagane steel]]
* [[Ferrous metallurgy]]
* [[Iron pillar of Delhi]]
* [[Pattern welding]]

==References==
{{reflist}}

==Further reading==
* {{cite journal |last=Srinivasan |first=Sharada |title=Wootz crucible steel: a newly discovered production site in South India |journal=Papers from the Institute of Archaeology |year=1994 |volume=5 |pages=49–59 |doi=10.5334/pia.60|url=https://www.pia-journal.co.uk/jms/article/download/pia.60/142 |doi-access=free }}
* {{cite journal |last1=Srinivasan |first1=S. |last2=Griffiths |first2=D. |title=South Indian wootz: evidence for high-carbon steel from crucibles from a newly identified site and preliminary comparisons with related finds |journal=Material Issues in Art and Archaeology |volume=462}}
* {{cite book |title=Den skapande människan |trans-title=The creative mind |first=Staffan |last=Hansson |year=2002 |page=81 |location=Lund, Sweden |publisher=[[Studentlitteratur]] AB |language=sv |isbn=978-9-14402-148-5}}
* [https://archive.today/20121215002236/http://dsal.uchicago.edu/cgi-bin/philologic/getobject.pl?c.1:1:3912.tamillex urukku - from the Tamil Lexicon, University of Madras]
* {{cite journal |title=Special Issue: History and Characteristics of Wootz Steel in India and Abroad |journal=Indian Journal of History of Science |volume=42 |number=3 |date=September 2007 |url=http://insa.nic.in/UI/Journalarticle.aspx?jid=Mw==&&VID=MzU=&&IsNm=SXNzdWUgMw==}}
* {{cite book |last1=Srinivasan |first1=Sharada |last2=Ranganathan |first2=Srinivasan |title=India's Legendary Wootz Steel: an advanced material of the ancient world |location=Bangalore |publisher=National Institute of Advanced Studies and Indian Institute of Science |year=2004}}
* {{cite journal |first=J. D. |last=Verhoeven |title=The Mystery of Damascus Blades |journal=[[Scientific American]] |pages=74–79 |date=January 2001 |volume=284 |issue=1 |jstor=26059015 |doi=10.1038/scientificamerican0101-74|pmid=11132427 |bibcode=2001SciAm.284a..74V }}

==External links==
* {{cite journal |url=http://www.tms.org/pubs/journals/JOM/9809/Verhoeven-9809.html |first1=J.D. |last1=Verhoeven |first2=A.H. |last2=Pendray |first3=W.E. |last3=Dauksch |title=The key role of impurities in ancient Damascus steel blades |journal=[[JOM (journal)|JOM]] |volume=50 |number=9 |year=1998 |pages=58–64 |doi=10.1007/s11837-998-0419-y|bibcode=1998JOM....50i..58V |s2cid=135854276 }}
* {{cite journal |last1=Verhoeven |first1=J.D. |last2=Pendray |first2=A.H. |last3=Dauksch |first3=W.E. |title=The continuing study of damascus steel: Bars from the alwar armory |journal=JOM |date=September 2004 |volume=56 |number=9 |pages=17–20
|doi=10.1007/s11837-004-0193-4 |bibcode=2004JOM....56i..17V |s2cid=137555792 }}
* {{cite journal |first=J.D. |last=Verhoeven |title=Pattern Formation in Wootz Damascus Steel Swords and Blades |journal=Indian Journal of History of Science |volume=42 |issue=4 |pages=559–574 |year=2007 |url=http://insa.nic.in/writereaddata/UpLoadedFiles/IJHS/Vol42_4_2_JVerhoeven.pdf}}
* [http://www.wootz.co Wootz Militaria]
* Archived at [https://ghostarchive.org/varchive/youtube/20211211/HvRqYE0ba-A Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20130507110035/http://www.youtube.com/watch?v=HvRqYE0ba-A&gl=US&hl=en Wayback Machine]{{cbignore}}: {{Cite AV media |url=https://www.youtube.com/watch?v=HvRqYE0ba-A |title=Wootz Ep 4: Making Wootz Steel |first=Niels |last=Provos |work=YouTube |date=3 May 2013}}{{cbignore}}
* Archived at [https://ghostarchive.org/varchive/youtube/20211211/OP8PCkcBZU4 Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20180603051802/https://www.youtube.com/watch?v=OP8PCkcBZU4 Wayback Machine]{{cbignore}}: {{Cite AV media |url=https://www.youtube.com/watch?v=OP8PCkcBZU4 |title=The Secrets of Wootz Damascus Steel |first=Mike |last=Loades |author-link=Mike Loades |first2=Al |last2=Pendray |date=21 November 2017 |work=YouTube}}{{cbignore}}
* {{cite patent |country=US |title=Method of making "Damascus" blades |number=5185044 |url=https://www.google.com/patents/US5185044 |invent1=Verhoeven, J.D. |invent2=Pendray, A.H. |pubdate=9 February 1993}}

{{Chera dynasty topics}}

[[Category:Steels]]
[[Category:History of India]]
[[Category:Indian inventions]]
[[Category:History of metallurgy]]
[[Category:Economic history of Tamil Nadu]]
[[Category:Chera dynasty]]
[[Category:Tamilakam]]

Wootz steel - Revision history

Ajay Kumar: Created a new article