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Mineralogy (Samskrit: धातुशास्त्रम्) or metallurgy discusses the chemistry of Dhatus (minerals), their properties, composition, reactions, combination products namely alloys and their uses. A related topic, mining of metals, involves the chemistry of extraction from ores, smelting and forging activities. History of mining in the Indian subcontinent can be traced back to pre-Harappan period where the evidence of earliest settlements of farming communities using metal implements have been found.<ref name=":0">Singh. R. D, (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D. by A. K. Bag.'' New Delhi: Indian National Science Academy. (Chapter Mining: Page 48 - ) </ref>  
 
Mineralogy (Samskrit: धातुशास्त्रम्) or metallurgy discusses the chemistry of Dhatus (minerals), their properties, composition, reactions, combination products namely alloys and their uses. A related topic, mining of metals, involves the chemistry of extraction from ores, smelting and forging activities. History of mining in the Indian subcontinent can be traced back to pre-Harappan period where the evidence of earliest settlements of farming communities using metal implements have been found.<ref name=":0">Singh. R. D, (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D. by A. K. Bag.'' New Delhi: Indian National Science Academy. (Chapter Mining: Page 48 - ) </ref>  
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Bharatavarsha is known for its use of gold and silver for jewelry and making ornamental vessels for domestic use with silver. Copper tools, such as axes, sickles are found in many archaeological sites indicating that many farming tribes and agricultural communities were using them. Metallurgy of copper and its alloys (brass and bronze) was highly developed during this period. A remarkable use of brass was made in the constructional work of an unfinished Vihara made near Nalanda (Bihar). Thus many archaeological revelations have unearthed valuable knowledge pertaining to sulbashastra (geology) and dhatushastra (metallurgy) of the ancients.<ref name=":0" /> [[File:Sushruta's Surgical Tools Made of Iron.PNG|thumb|Ancient Surgical tools in India|475.234x475.234px]]
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Bharatavarsha is known for its use of gold and silver for jewelry and making ornamental vessels for domestic use with silver. Copper tools, such as axes, sickles are found in many archaeological sites indicating that many farming tribes and agricultural communities were using them. Metallurgy of copper and its alloys (brass and bronze) was highly developed during this period. A remarkable use of brass was made in the constructional work of an unfinished Vihara made near Nalanda (Bihar). Thus many archaeological revelations have unearthed valuable knowledge pertaining to sulbashastra (geology) and dhatushastra (metallurgy) of the ancients.<ref name=":0" /> [[File:Sushruta's Surgical Tools Made of Iron.PNG|thumb|Ancient Surgical tools in India|500x500px]]
 
== Introduction ==
 
== Introduction ==
 
Metals, Minerals and ores are mentioned by the terms dhatu (धातुः) khanija (खानिजम्) and the chemistry involved is termed Khanija-rasayana (खानिजरसायनम्). A mineral is defined in modern terms as follows<ref name=":1">''[http://eprints.nmlindia.org/5802/1/1-24.PDF Minerals and Their Exploitation in Ancient and Pre-modern India]'' by Prof. A. K. Biswas</ref><blockquote>''"As we knew mineral is a naturally occurring crystalline element or a compound having definite chemical composition, and formed as a product of inorganic processes."''</blockquote>The scientific analysis of the archaeological and literary evidences points to the debunking of the aryan invasion myth in the recent times.<ref name=":1" /> <blockquote>''A number of experts have concluded that the collapse of the Harappan civilization was not on account of any 'foreign invasion' but essentially due to repeated floods, tectonic movement leading to the drying up and disappearance of the Sarasvati river, civil war, loss of trade etc.''</blockquote>Just like pottery, metals in antiquity is also linked to the history of a civilization. In the ancient past, the first metals to be utilized were those found in the native or elemental state, and then progressively those metals were used which could be easily extracted or smelted from their ores. The smelting of metals, which were more difficult to extract from ores, was mastered later. Most of the metals and elements indicated in the Periodic Table were in fact identified only in the last few centuries.   
 
Metals, Minerals and ores are mentioned by the terms dhatu (धातुः) khanija (खानिजम्) and the chemistry involved is termed Khanija-rasayana (खानिजरसायनम्). A mineral is defined in modern terms as follows<ref name=":1">''[http://eprints.nmlindia.org/5802/1/1-24.PDF Minerals and Their Exploitation in Ancient and Pre-modern India]'' by Prof. A. K. Biswas</ref><blockquote>''"As we knew mineral is a naturally occurring crystalline element or a compound having definite chemical composition, and formed as a product of inorganic processes."''</blockquote>The scientific analysis of the archaeological and literary evidences points to the debunking of the aryan invasion myth in the recent times.<ref name=":1" /> <blockquote>''A number of experts have concluded that the collapse of the Harappan civilization was not on account of any 'foreign invasion' but essentially due to repeated floods, tectonic movement leading to the drying up and disappearance of the Sarasvati river, civil war, loss of trade etc.''</blockquote>Just like pottery, metals in antiquity is also linked to the history of a civilization. In the ancient past, the first metals to be utilized were those found in the native or elemental state, and then progressively those metals were used which could be easily extracted or smelted from their ores. The smelting of metals, which were more difficult to extract from ores, was mastered later. Most of the metals and elements indicated in the Periodic Table were in fact identified only in the last few centuries.   
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Chandogya Upanisad recognised that metals have intrinsic properties irrespective of the shapes that these may assume (Cha. Up 6.1.5 & 6). It stipulated that one can join gold with the help of borax, lead with the help of tin 'etc.<blockquote>तद्यथा लवणेन सुवर्णँ सन्दध्यात्सुवर्णेन रजतँ रजतेन त्रपु त्रपुणा सीसँ सीसेन लोहं लोहेन दारु दारु चर्मणा ॥ ७ ॥ (Chan. Upan. 4.17.7)<ref>Chandogya Upanishad ([https://sa.wikisource.org/wiki/%E0%A4%9B%E0%A4%BE%E0%A4%A8%E0%A5%8D%E0%A4%A6%E0%A5%8B%E0%A4%97%E0%A5%8D%E0%A4%AF%E0%A5%8B%E0%A4%AA%E0%A4%A8%E0%A4%BF%E0%A4%B7%E0%A4%A6%E0%A5%8D/%E0%A4%85%E0%A4%A7%E0%A5%8D%E0%A4%AF%E0%A4%BE%E0%A4%AF%E0%A4%83_%E0%A5%AA Adhyaya 4 Khanda 17])</ref></blockquote>Summary: Just as one would join together (pieces of) gold by borax, by gold silver, by silver tin, by tin lead, by lead iron, by iron wood or by leather.<ref>Mm. Ganganath Jha. (1923) ''Chhandogya Upanishad and Sri Sankara's Commentary.'' Madras: The India Printing Press. (Page 261)</ref>
 
Chandogya Upanisad recognised that metals have intrinsic properties irrespective of the shapes that these may assume (Cha. Up 6.1.5 & 6). It stipulated that one can join gold with the help of borax, lead with the help of tin 'etc.<blockquote>तद्यथा लवणेन सुवर्णँ सन्दध्यात्सुवर्णेन रजतँ रजतेन त्रपु त्रपुणा सीसँ सीसेन लोहं लोहेन दारु दारु चर्मणा ॥ ७ ॥ (Chan. Upan. 4.17.7)<ref>Chandogya Upanishad ([https://sa.wikisource.org/wiki/%E0%A4%9B%E0%A4%BE%E0%A4%A8%E0%A5%8D%E0%A4%A6%E0%A5%8B%E0%A4%97%E0%A5%8D%E0%A4%AF%E0%A5%8B%E0%A4%AA%E0%A4%A8%E0%A4%BF%E0%A4%B7%E0%A4%A6%E0%A5%8D/%E0%A4%85%E0%A4%A7%E0%A5%8D%E0%A4%AF%E0%A4%BE%E0%A4%AF%E0%A4%83_%E0%A5%AA Adhyaya 4 Khanda 17])</ref></blockquote>Summary: Just as one would join together (pieces of) gold by borax, by gold silver, by silver tin, by tin lead, by lead iron, by iron wood or by leather.<ref>Mm. Ganganath Jha. (1923) ''Chhandogya Upanishad and Sri Sankara's Commentary.'' Madras: The India Printing Press. (Page 261)</ref>
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Arthashastra defines the following as metals
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काल-अयस-ताम्र-वृत्त-कंस-सीस-त्रपु-वैकृन्तक-आर्कूटानि लोहानि ।। ०२.१७.१४ ।।
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Káláyasa (iron), támra (copper), vritta (?), kámsya (bronze), sísa (lead), trapu (tin), vaikrintaka (mercury ?), and árakuata (brass), are metals.<ref>Arthashastra by Kautilya ([https://sa.wikisource.org/wiki/%E0%A4%85%E0%A4%B0%E0%A5%8D%E0%A4%A5%E0%A4%B6%E0%A4%BE%E0%A4%B8%E0%A5%8D%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AE%E0%A5%8D/%E0%A4%85%E0%A4%A7%E0%A4%BF%E0%A4%95%E0%A4%B0%E0%A4%A3%E0%A4%AE%E0%A5%8D_%E0%A5%A8/%E0%A4%85%E0%A4%A7%E0%A Adhikarana 2 Adhyaya 17])</ref>
    
It is interesting to note that ancient texts have mentioned many matters regarding the existence and usage of metals, their properties, nature and their extraction. Debiprasad Chattopadhyaya acclaimed [[Uddalaka (उद्दालकः)|Uddalaka Aruni]] as ''''the first scientist in the world'''<nowiki/>'. Uddalaka Aruni as mentioned in the Chandogya Upanishad propounded that everything in the universe including man evolved out of three elements, and even mind is a product of matter. According to Chattopadhyaya Maharshi Uddalaka preceded Theles of Greece by nearly two centuries.<ref name=":1" /><ref>Chattopadhyaya, Debiprasad. (1991) ''History of Science and Technology in Ancient India ll Formation of the Theoretical Fundamentals of Natural Science.'' Calcutta: Firma KLM Pvt. Ltd., </ref>
 
It is interesting to note that ancient texts have mentioned many matters regarding the existence and usage of metals, their properties, nature and their extraction. Debiprasad Chattopadhyaya acclaimed [[Uddalaka (उद्दालकः)|Uddalaka Aruni]] as ''''the first scientist in the world'''<nowiki/>'. Uddalaka Aruni as mentioned in the Chandogya Upanishad propounded that everything in the universe including man evolved out of three elements, and even mind is a product of matter. According to Chattopadhyaya Maharshi Uddalaka preceded Theles of Greece by nearly two centuries.<ref name=":1" /><ref>Chattopadhyaya, Debiprasad. (1991) ''History of Science and Technology in Ancient India ll Formation of the Theoretical Fundamentals of Natural Science.'' Calcutta: Firma KLM Pvt. Ltd., </ref>
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== Gem - Minerals ==
 
== Gem - Minerals ==
 
Earliest complete description of the gems is given in texts such as Arthashastra and Brhat Samhita.<blockquote>वज्रैन्द्रनील-मरकतकर्केतरपद्मरागरुधिरऽख्याः ।  वैदूर्य[क्.वैडूर्य]पुलकविमलकराजमणिस्फटिकशशिकान्ताः ।। </blockquote><blockquote>सौगन्धिक-गोमेदक-शङ्ख-महानील-पुष्परागऽख्याः । ब्रह्ममणि-ज्योतीरस-सस्यक-मुक्ता-प्रवालानि ।। (Brht. Samh. 80.4-5)</blockquote>Meaning: The following are the gems: Vajra (Diamonds), Indranila (Sapphire), Marakata (Emerald), Arkata (Agate), Padmaraga (Ruby), Rudhira (Blood-stone), Vaidurya (Beryl), Pulaka (Amethyst), Vimalaka, Rajamani, Spatika (Quartz), Shashikanta (moon-gem), Saugandhika, Gomedaka (Zircon), Shankha (Conch Shell), Mahanila (Azure), Pushparaga (Topaz), Brahma-mani, Jyoteerasa, Sasyaka, Mukta (Pearl), Pravala (Coral).<ref name=":3" />
 
Earliest complete description of the gems is given in texts such as Arthashastra and Brhat Samhita.<blockquote>वज्रैन्द्रनील-मरकतकर्केतरपद्मरागरुधिरऽख्याः ।  वैदूर्य[क्.वैडूर्य]पुलकविमलकराजमणिस्फटिकशशिकान्ताः ।। </blockquote><blockquote>सौगन्धिक-गोमेदक-शङ्ख-महानील-पुष्परागऽख्याः । ब्रह्ममणि-ज्योतीरस-सस्यक-मुक्ता-प्रवालानि ।। (Brht. Samh. 80.4-5)</blockquote>Meaning: The following are the gems: Vajra (Diamonds), Indranila (Sapphire), Marakata (Emerald), Arkata (Agate), Padmaraga (Ruby), Rudhira (Blood-stone), Vaidurya (Beryl), Pulaka (Amethyst), Vimalaka, Rajamani, Spatika (Quartz), Shashikanta (moon-gem), Saugandhika, Gomedaka (Zircon), Shankha (Conch Shell), Mahanila (Azure), Pushparaga (Topaz), Brahma-mani, Jyoteerasa, Sasyaka, Mukta (Pearl), Pravala (Coral).<ref name=":3" />
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=== सुवर्णम् हिरण्यम् वा ॥ Gold (''Aurum'' - Au) ===
 
=== सुवर्णम् हिरण्यम् वा ॥ Gold (''Aurum'' - Au) ===
Arthashastra describes the qualities of the gold ore thus<blockquote>पीतकास्-ताम्रकास्ताम्र-पीतका वा भूमि-प्रस्तर-धातवो भिन्ना ..... बहुफेनधूमाश्च सुवर्ण-धातवः प्रतीवाप-अर्थास्ताम्ररूप्य-वेधनाः ।। ०२.१२.०५ ।। (Arth. Shast. 2.12.5)<ref name=":6" /></blockquote>''"Those ores which are obtained from plains or slopes of mountains; which are either yellow or as red as copper or reddish yellow; which are disjoined and marked with blue lines; which have the colour of black beans (masha, Phraseolus Radiatus), green beans (mudga, Phraseolus Mungo), and sesamum; which are marked with spots like a drop of curd and resplendent as turmeric, yellow myrobalan, petals of a lotus, acquatic plant, the liver or the spleen; which possess a sandy layer within them and are marked with figures of a circle or a svastika; which contain globular masses (sagulika); and which, when roasted do not split, but emit much foam and smoke are the ores of gold (suvarnadhátavah), and are used to form amalgams with copper or silver (pratívápárthasté stámrarúpyavedharáh)".''<ref name=":7">Shamasastry. R. Kautilya's Arthashastra with English Translation. (Pages 111 - )</ref>
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Arthashastra describes the qualities of the gold ore thus<blockquote>पीतकास्-ताम्रकास्ताम्र-पीतका वा भूमि-प्रस्तर-धातवो भिन्ना ..... बहुफेनधूमाश्च सुवर्ण-धातवः प्रतीवाप-अर्थास्ताम्ररूप्य-वेधनाः ।। ०२.१२.०५ ।। (Arth. Shast. 2.12.5)<ref name=":6" /></blockquote>''"Those ores which are obtained from plains or slopes of mountains; which are either yellow or as red as copper or reddish yellow; which are disjoined and marked with blue lines; which have the colour of black beans (masha, Phraseolus Radiatus), green beans (mudga, Phraseolus Mungo), and sesamum; which are marked with spots like a drop of curd and resplendent as turmeric, yellow myrobalan, petals of a lotus, acquatic plant, the liver or the spleen; which possess a sandy layer within them and are marked with figures of a circle or a svastika; which contain globular masses (sagulika); and which, when roasted do not split, but emit much foam and smoke are the ores of gold (suvarnadhátavah), and are used to form amalgams with copper or silver (pratívápárthasté stámrarúpyavedharáh)".''<ref name=":7">Shamasastry. R. Kautilya's Arthashastra with English Translation. (Pages 111 - 115)</ref>
    
Early reference to gold is to be found in the Rigveda samhita. However, not many gold artifacts dating to Pre-Harappan period have been reported although in Rgveda Gold and its alloys with Ag and Cu have been mentioned in many places, such as, 1-85.9, 88.5, 67.3; II-37.9; V-54.15, 57.1, 60.4; VIII - 7.27-32 etc. In Vedic literature this metal has been mentioned as Hiranya (हिरण्यम्) probably because of its high corrosion and oxidation resistance and the practice of its preservation through generations.<ref name=":5">Bhanu Prakash (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D. by A. K. Bag.'' New Delhi: Indian National Science Academy. (Chapter Metals and Metallugy: Page 80 )</ref>
 
Early reference to gold is to be found in the Rigveda samhita. However, not many gold artifacts dating to Pre-Harappan period have been reported although in Rgveda Gold and its alloys with Ag and Cu have been mentioned in many places, such as, 1-85.9, 88.5, 67.3; II-37.9; V-54.15, 57.1, 60.4; VIII - 7.27-32 etc. In Vedic literature this metal has been mentioned as Hiranya (हिरण्यम्) probably because of its high corrosion and oxidation resistance and the practice of its preservation through generations.<ref name=":5">Bhanu Prakash (1997) ''History of Technology in India, Vol. 1, From Antiquity to c. 1200 A.D. by A. K. Bag.'' New Delhi: Indian National Science Academy. (Chapter Metals and Metallugy: Page 80 )</ref>
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* Gold coating of copper ornaments was very popular
 
* Gold coating of copper ornaments was very popular
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=== रसः ॥ Mercury ===
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=== रसः वैकृन्तक वा ॥ Mercury ===
Ore of Mercury: Cinnabar (Hingula)
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Arthashastra defines the mercury ore thus<blockquote>काक-अण्ड-भुज-पत्त्र-वर्णो वा वैकृन्तक-धातुः ।। ०२.१२.१६ ।। (Arth. Shast. 2.12.16)<ref name=":6" /></blockquote>''Those ores which are of the colour of the leaf of kánda (Artemisia Indica) or of the leaf of birch are the ores of vaikrintaka''.<ref name=":7" />
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Mercury is a metal that has been of great alchemical importance in ancient times. It is a volatile metal, which is easily produced by heating cinnabar followed by the downward distillation of mercury vapour. Some of the earliest literary references to the use of mercury distillation come from Indian treatises such as the Arthashastra of Kautilya. Ayurvedic texts have presented the science of using mercury, as [[Rasashastra (रसशास्त्रम्)|Rasashastra]].
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Mercury is a metal that has been of great alchemical importance in ancient times. Ayurvedic texts have presented the science of using mercury, as [[Rasashastra (रसशास्त्रम्)|Rasashastra]].
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==== Extraction Process ====
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Mercury Ores: Cinnabar (Hingula)
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It is a volatile metal, which is easily produced by heating cinnabar followed by the downward distillation of mercury vapour. Some of the earliest literary references to the use of mercury distillation come from Indian treatises such as the Arthashastra of Kautilya.  
 
* Sindhur or Vermilion was Cinnabar, mercuric sulphide, was used to make the red/maroon mark on the forehead as described by Charaka.
 
* Sindhur or Vermilion was Cinnabar, mercuric sulphide, was used to make the red/maroon mark on the forehead as described by Charaka.
[[File:Delhi Iron Pillar.png|thumb|Delhi Iron Pillar " The Rustless Wonder"|489.961x489.961px]]
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[[File:Delhi Iron Pillar.png|thumb|Delhi Iron Pillar " The Rustless Wonder"|588x588px]]
    
=== अयस् ॥ Iron (''Ferrum - Fe'') ===
 
=== अयस् ॥ Iron (''Ferrum - Fe'') ===
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* Munda Loha (cast iron)
 
* Munda Loha (cast iron)
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==== Tools and Implements ====
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==== Important Landmarks  ====
 
'''Surgical tools''' : The Susruta Samhita has mentioned the method of fabrication of more than 100 surgical tools made of Fe-C alloys and the process of heat treatment to obtain razor sharp edge capable of splitting hair into two halves longitudinally.
 
'''Surgical tools''' : The Susruta Samhita has mentioned the method of fabrication of more than 100 surgical tools made of Fe-C alloys and the process of heat treatment to obtain razor sharp edge capable of splitting hair into two halves longitudinally.
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* Monumental Iron pillar at Dhar in Central India, and Kodachadri in coastal Karnataka and Iron beams of the Konark temple.
 
* Monumental Iron pillar at Dhar in Central India, and Kodachadri in coastal Karnataka and Iron beams of the Konark temple.
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=== Zinc ===
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=== यशद ॥ Zinc (''Zinc - Zn'') ===
The earliest firm evidence for the production of metallic zinc comes from India. Of the eight metals used in antiquity zinc is one of the most difficult to smelt since it volatalizes at about the same temperature of around 1000 °C that is needed to smelt zinc ore. As a result, it forms as a vapour in the furnace which would immediately get reoxidised and hence the pure form is lost. So there are very few references to metallic zinc in early treatises. In India there is unique evidence for the extensive and semi-industrial production of zinc at the Zawar area of Rajasthan. An ingenious method was devised of downward distillation of the zinc vapour formed after smelting zinc ore using specifically designed retorts with condensers and furnaces. The zinc vapour could be cooled down drastically to get a melt that could solidify to zinc metal. The Rasaratnakara, Nagarjuna describes this method of production of zinc.
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Arthashastra does not specifically mention about Zinc ores. Zinc is silvery white in colour and very hard and brittle owing to its close packed hexagonal crystal structure. The earliest firm evidence for the production of metallic zinc comes from India. Of the eight metals used in antiquity zinc is one of the most difficult to smelt since it volatalizes at about the same temperature of around 1000°C that is needed to smelt zinc ore. As a result, it forms as a vapour in the furnace which would immediately get reoxidised and hence the pure form is lost. So there are very few references to metallic zinc in early treatises.  
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In view of the Indian quest for substitute gold, the name for zinc was changed from rasaka (that which is distilled like rasa or mercury) to yashada (that which gives yasha or fame alluding to gold). It is this later Sanskrit word Yashada which was converted to dasta in the other Indian languages and 'zinc' in the European languages.<ref name=":1" />
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==== Extraction Process ====
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* Zinc Ores : Calamine (ZnCO<sub>3</sub>) and Sphalerite (ZnS)
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* Downward draft reduction - distillation process
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In India there is unique evidence for the extensive and semi-industrial production of zinc at the Zawar area of Rajasthan. An ingenious method was devised of downward distillation of the zinc vapour formed after smelting zinc ore using specifically designed retorts with condensers and furnaces. The zinc vapour could be cooled down drastically to get a melt that could solidify to zinc metal. The Rasaratnakara, Nagarjuna describes this method of production of zinc.
 
* Zawar Zinc mines using downward distillation process to produce metallic zinc.
 
* Zawar Zinc mines using downward distillation process to produce metallic zinc.
त्रपु ॥ Tin  
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=== त्रपु ॥ Tin (''Stannum - Sn'') ===
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Arthashastra describes the qualities of the Tin ore thus<blockquote>ऊषर-कर्बुरः पक्व-लोष्ठ-वर्णो वा त्रपु-धातुः ।। ०२.१२.१४ ।। (Arth. Shast. 2.12.14)<ref name=":6" /></blockquote>''Those ores which are as variegated in colour as saline soil or which have the colour of a burnt lump of earth are the ores of tin''.<ref name=":7" />
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Mention of Tin(Trapu,Vanga) has been made in Vedas (Yajurveda 30.14) but no extraction process or specific use has been described till the introduction of bronze. In India very meagre deposits of tin bearing ore have been reported from Hazaribagh and Chota Nagpur area and most probably this metal or its oxide mineral Cassiterite was brought from Burma or Malaya.
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=== लोहाध्यक्षः ॥ Lohadhyaksha ===
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Arthashastra further describes the duties of the Lohadhyaksha who is the appointed person to carry on the activities related to metals. <blockquote>लोह-अध्यक्षस्ताम्र-सीस-त्रपु-वैकृन्तकारकूट-वृत्त-कंस-ताल-लोह-कर्म-न्तान्कारयेत् । लोह-भाण्ड-व्यवहारं च ।। ०२.१२.२३ ।। (Arth. Shast. 2.12.23)<ref name=":6" /></blockquote>''The superintendent of metals (lóhádhyakshah) shall carry on the manufacture of copper, lead, tin, vaikrintaka (mercury [?]), árakúta (brass), vritta(?); kamsa (bronze or bell-metal), tála (sulphurate of arsenic), and lodhra (?), and also of commodities (bhánda) from them.''<ref name=":7" />
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== Alloys of Metals ==
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The concepts of alloy or mixed metal (mishra loha or yukta) and heat-treatment by quenching (gastrapana) were elaborated in Rasaratnasamucchaya. Alloys of five metals (panchalohas) and eight metals (ashtadhatu) were developed mostly for making auspicious images.
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=== Kamsya Bronze (Tin and Copper) ===
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The earlier bronze was most probably made by co-reduction of mixed ore of Casseterite and Cuprite or oxidized Chalcopyrite.
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=== Arakuta Brass (Zinc and Copper) ===
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Taxila provides the evidences for the brass and zinc artifacts in India.  Indian craftsmen continued to make brass through the cementation route, namely reduction of copper ore and zinc ore in the same furnace simultaneously. While zinc oxide is easily reducible at the usual temperature of the smelting furnace, the metal zinc is produced in the vapour state, since it has a low boiling point 917°C. Zinc vapour gets absorbed in copper to produce cementation brass.
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The Sanskrit term for gold-like yellow brass was Pita-tala (yellow alloy) or pitala.<ref name=":1" />
    
== References ==
 
== References ==
 
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