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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>  

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>

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 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>

=== Origin of Metals and Gems ===

== 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" />

=== Origin ===

There are many legends about the origin of metals and gems in the vaidika vangmaya. Many puranas discuss about the origin of gold from the semen of Shiva.  

There are many legends about the origin of metals and gems in the vaidika vangmaya. Many puranas discuss about the origin of gold from the semen of Shiva.  

In his Brhat Samhita, Varahamihira gave a scientific explanation that the gems were caused by the characteristic qualities of the earth. <blockquote>रत्नानि बलाद्दैत्याद्दधीचितोऽन्ये वदन्ति जातानि । केचिद्भुवः स्वभावाद्वैचित्र्यं प्राहुरुपलानाम् ।। (Brht. Samh. 80.3)</blockquote>Meaning: Gems, they say, were born of the bones of the daitya Bala; while others state that they were born of Dadichi; yet others say that the wonderful variety of germs is caused by the characteristic qualities of the earth.<ref name=":3">Sastri, V. Subrahmanya and Bhat. M. Ramakrishna, (1946) ''Varahamihira's Brihat Samhita with an English Translation and Notes.'' Bangalore City: V. B. Soobbiah and Sons (Page 628 - 629)</ref>

In his Brhat Samhita, Varahamihira gave a scientific explanation that the gems were caused by the characteristic qualities of the earth. <blockquote>रत्नानि बलाद्दैत्याद्दधीचितोऽन्ये वदन्ति जातानि । केचिद्भुवः स्वभावाद्वैचित्र्यं प्राहुरुपलानाम् ।। (Brht. Samh. 80.3)</blockquote>Meaning: Gems, they say, were born of the bones of the daitya Bala; while others state that they were born of Dadichi; yet others say that the wonderful variety of germs is caused by the characteristic qualities of the earth.<ref name=":3">Sastri, V. Subrahmanya and Bhat. M. Ramakrishna, (1946) ''Varahamihira's Brihat Samhita with an English Translation and Notes.'' Bangalore City: V. B. Soobbiah and Sons (Page 628 - 629)</ref>

== Gem-Minerals ==

=== Samskrit Etymological Roots ===

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" />

 

The names of many minerals and elements that we find in European languages were originally derived from Samskrit, having strong etymological roots. A few samskrit origins of minerals are as follows.<ref name=":2" />  

The names of many minerals and elements that we find in European languages were originally derived from Samskrit, having strong etymological roots. A few samskrit origins of minerals are as follows.<ref name=":2" />  

# Corundum is derived from "कुरुविन्दः । kuruvinda", meaning that which abrades.   

# Corundum is derived from "कुरुविन्दः । kuruvinda", meaning that which abrades.   

|Iron, manganese etc.possibly complexed with organic matter, so that the colour is perishable on heating.

|Iron, manganese etc.possibly complexed with organic matter, so that the colour is perishable on heating.

|}

|}

A few non-gem minerals of commercial importance in ancient India:  

A few non-gem minerals or metals of commercial importance in ancient India: include the following list:<ref name=":2" /> 

adrija (bitumen), abhraka (mica), kajjali (cinnabar), karpurarasa (calomel), kamksi (alum), kasisa (green vitriol or ferrous sulphate), kharpara (zinc ore), gandhaka (sulphur), gandhara (red lead), chulika lavana (sal ammoniac), tankana (borax), tala (orpiment), tutthaka (blue vitriol), nilanjana (stibnite), makaradhvaja (mercuric sulphide), manahsila (realgar) maksika (pyrite), swarnamakshika (chalcopyrite), mrddarasrnga (anglesite or litharge), rasaka (calamine), rasakarpura (mercuric chloride), rasasindura (mercuric sulphide), rasanjana (stibnite), varatika (marine nodule), vahnimrttika (fire-clay), vimalaka (pyrite), kamsya vimala (arsenopyrite), silajatu (bitumen), sarjika mrttika (river-bed alkaline reh), sasyaka (blue vitriol), sisaja (red lead), suvarcika (borax), srotanjana or sohta (carrollite), haritala (orpiment) etc.

adrija (bitumen), abhraka (mica), kajjali (cinnabar), karpurarasa (calomel), kamksi (alum), kasisa (green vitriol or ferrous sulphate), kharpara (zinc ore), gandhaka (sulphur), gandhara (red lead), chulika lavana (sal ammoniac), tankana (borax), tala (orpiment), tutthaka (blue vitriol), nilanjana (stibnite), makaradhvaja (mercuric sulphide), manahsila (realgar) maksika (pyrite), swarnamakshika (chalcopyrite), mrddarasrnga (anglesite or litharge), rasaka (calamine), rasakarpura (mercuric chloride), rasasindura (mercuric sulphide), rasanjana (stibnite), varatika (marine nodule), vahnimrttika (fire-clay), vimalaka (pyrite), kamsya vimala (arsenopyrite), silajatu (bitumen), sarjika mrttika (river-bed alkaline reh), sasyaka (blue vitriol), sisaja (red lead), suvarcika (borax), srotanjana or sohta (carrollite), haritala (orpiment) etc.

The commonly used eight metals in antiquity are gold, silver, copper, iron, tin, lead, zinc and mercury.<ref name=":4">Srinivasan, Sharada and Ranganathan, Srinivasa. (2013) ''[http://eprints.nias.res.in/374/1/B8-2013%20Minerals%20and%20Metals%20Heritage%20of%20India.pdf Minerals and Metals Heritage of India.]'' Bangalore:National Institute of Advanced Studies.</ref>  

The present section reviews the important metals, their qualities, ores and interesting points about their role since ancient times. One of the ancient texts that gives a comprehensive view about metals is Kautilya's Arthashastra. Though a book on polity and administration, it gives a great deal of information regarding many aspects of life such as agriculture, economy, trade, metals and gems, occupations, weapons and spies and many other interesting out of the norm situations. A summary of the description of the ores, management of mines, rock veins of minerals, metals (gold silver copper and their alloys) with their extraction and working, as well as of alloys, information of fabrication of metallic artefacts are found in the text. Kautilya outlines the duties of the Superintendent of Mines (लोहाध्यक्षः) and gives him the details of the ores of metals and their fabrications in Adhyaya 12 of Adhikarana 2. Some common observations about the ores are also mentioned by Kautilya such as  <blockquote>सर्व-धातूनां गौरव-वृद्धौ सत्त्व-वृद्धिः ।। ०२.१२.०७ ।। (Arth. Shast. 2.12.7)<ref name=":6">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 12])</ref></blockquote>The heavier the ores, greater will be the quantity of metal in them (sattva-vrddhi)

The commonly used eight metals in antiquity are gold, silver, copper, iron, tin, lead, zinc and mercury.<ref name=":4">Srinivasan, Sharada and Ranganathan, Srinivasa. (2013) ''[http://eprints.nias.res.in/374/1/B8-2013%20Minerals%20and%20Metals%20Heritage%20of%20India.pdf Minerals and Metals Heritage of India.]'' Bangalore:National Institute of Advanced Studies.</ref>

The present section reviews the important metals, their qualities, ores and interesting points about their role since ancient times. One of the ancient texts that gives a comprehensive view about metals is Kautilya's Arthashastra. Though a book on polity and administration, it gives a great deal of information regarding many aspects of life such as agriculture, economy, trade, metals and gems, occupations, weapons and spies and many other interesting out of the norm situations. A summary of the description of the ores, management of mines, rock veins of minerals, metals (gold silver copper and their alloys) with their extraction and working, as well as of alloys, information of fabrication of metallic artefacts are found in the text. Kautilya outlines the duties of the Superintendent of Mines (लोहाध्यक्षः) and gives him the details of the ores of metals and their fabrications in Adhyaya 12 of Adhikarana 2. Some common observations about the ores are also mentioned by Kautilya such as  <blockquote>सर्व-धातूनां गौरव-वृद्धौ सत्त्व-वृद्धिः ।। ०२.१२.०७ ।। (Arth. Shast. 2.12.7)<ref name=":6">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 12])</ref></blockquote>The heavier the ores, greater will be the quantity of metal in them (sattva-vrddhi)

=== सुवर्णम् हिरण्यम् वा ॥ Gold (''Aurum'' - Au) ===

=== सुवर्णम् हिरण्यम् वा ॥ Gold (''Aurum'' - Au) ===

Interestingly, as far as silver production goes, the Aravalli region in North-West India ranks amongst the few major ancient silver producing sites in the world.

Interestingly, as far as silver production goes, the Aravalli region in North-West India ranks amongst the few major ancient silver producing sites in the world.

=== सीसम् ॥ Lead ===

=== सीसम् ॥ Lead (''Plumbum - Pb'') ===

Arthashastra describes the qualities of the lead ore thus

Arthashastra describes the qualities of the lead ore thus<blockquote>काक-मोचकः कपोत-रोचना-वर्णः श्वेत-राजि-नद्धो वा विस्रः सीस-धातुः ।। ०२.१२.१३ ।। (Arth. Shast. 2.12.13)<ref name=":6" /></blockquote>''"Those ores which have the colour of kákamochaka (Solanum Indica), pigeon, or cow‟s bile, and which are marked with white lines and smell like raw meat are the ores of lead."''<ref name=":7" />

 

काक-मोचकः कपोत-रोचना-वर्णः श्वेत-राजि-नद्धो वा विस्रः सीस-धातुः ।। ०२.१२.१३ ।। (Arth. Shast. 2.12.13)<ref name=":6" />

The lead artifacts during the Harappan period reflect the fact that people were acquainted with lead ores (such as galena) and their smelting process which is simple on account of easy reducibility and low melting point of the metal. Like gold and silver, lead did not find extensive usage in tools and implements owing to its softness. It is one of the softest and heaviest metal having shining grey lustre which leaves a black streak on paper.  

 

The lead artifacts during the Harappan period have been reported showing that the people were acquainted with lead ores (such as galena) and their smelting process which is simple on account of easy reducibility and low melting point of the metal. Like gold and silver, lead did not find extensive usage in tools and implements owing to its softness. It is one of the softest and heaviest metal having shining grey lustre which leaves a black streak on paper.  

It is so soft that it can be scratched even with nail hence it’s use has been mostly for the manufacture of cheap jewellery dies or pattern for shaping other metals, and as a hardner in copper alloys.

It is so soft that it can be scratched even with nail hence it’s use has been mostly for the manufacture of cheap jewellery dies or pattern for shaping other metals, and as a hardner in copper alloys.

The  mineral-rich Aravalli region of Rajasthan was one of the important early lead mining regions in antiquity.

The  mineral-rich Aravalli region of Rajasthan was one of the important early lead mining regions in antiquity.

* Lead was used in making alloys of silver, copper

* Lead was used in making alloys of silver, copper etc

* Chief coinage metal around 1-2nd BCE.

* Chief coinage metal around 1-2nd BCE.

=== ताम्रम् ॥ Copper ===

=== ताम्रम् ॥ Copper (''Cuprum - Cu'') ===

Early copper artifacts are reported from the pre-Indus valley sites of Baluchistan, the northwestern part of Indian subcontinent. Evidence of ancient mining of copper ores was from the Khetri region of Rajasthan in India dating to about 3rd-2nd millennium BC. Huge quantities of copper objects such as blades, arrow-heads, fish hooks were found from the sites of Pre-harappan excavations. It may be asserted based on evidence that copper metallurgy was developed indigenously in the Indian subcontinent well before 4000 BC.<ref name=":1" /><ref name=":4" />

 

==== Extraction Process ====

Early copper artifacts are reported from the pre-Indus valley sites of Baluchistan, the northwestern part of Indian subcontinent. Evidence of ancient mining of copper ores was from the Khetri region of Rajasthan in India dating to about 3rd-2nd millennium BC. Huge quantities of copper objects such as blades, arrow-heads, fish hooks were found from the sites of Pre-harappan excavations. It may be asserted based on evidence that copper metallurgy was developed indigenously in the Indian subcontinent well before 4000 BC. This theory of indigenous discovery of copper production technology is further supported by the presence of 4.8% Nickel and 2.14% lead in the copper, artifacts found at the Harappan sites, whereas the Iranian copper is rich in Arsenic.<ref name=":1" /><ref name=":4" /><ref name=":5" />

* Ores of copper as pyrites was identified far before any other civilization.

* Ores of copper as pyrites was identified far before any other civilization.

* Oldest reference of use of indigenous copper metullurgy is found in Indian civilization

* Oldest reference of use of indigenous copper metullurgy is found in Indian civilization

=== रसः ॥ Mercury ===

=== रसः ॥ Mercury ===

[[File:Delhi Iron Pillar.png|thumb|Delhi  Iron Pillar " The Rustless Wonder"]]

[[File:Delhi Iron Pillar.png|thumb|Delhi  Iron Pillar " The Rustless Wonder"]]

=== अयस् ॥ Ayas (Iron) ===

=== अयस् ॥ Iron (''Ferrum - Fe'') ===

Ores of Iron : Haematite (Fe₂O₃), Magnetite (Fe₃O₄), Goethite (HFeO₂) and Limonite (FeO (OH)_n*H₂O).

Arthashastra describes the qualities of the Iron ore thus

 

खरुम्बः पाण्डु-रोहितः सिन्दु-वार-पुष्प-वर्णो वा तीक्ष्ण-धातुः ।। ०२.१२.१५ ।।(Arth. Shast. 2.12.14)<ref name=":6" />

Earliest Iron Age sites in India show that the discovery and use of iron started around 1200 BC indigenously and independently in at least three nuclear zones- Karnataka area in the south, U.P and Rajasthan area in the north and West Bengal-Bihar area in the north-east. The evidences of early experimentation justify the theory of indigenous origin. Since iron could not be melted and cast easily, carburization of thin sheets of iron in charcoal fire and subsequent lamination and forge-welding of alternate layers of uncarburized and carburized sheets proved to be a.spectacular and.useful Indian discovery made much before the era of laminated Egyptian knife dated 900-800 BC.<ref name=":1" />

 

Significant finding of archaeologists is that iron objects were totally absent in the Harappan and Mohenjadaro excavations.<ref name=":5" /> However, earliest Iron Age sites in India show that the discovery and use of iron started around 1200 BC indigenously and independently in at least three nuclear zones- Karnataka area in the south, U.P and Rajasthan area in the north and West Bengal-Bihar area in the north-east. The evidences of early experimentation justify the theory of indigenous origin. Since iron could not be melted and cast easily, carburization of thin sheets of iron in charcoal fire and subsequent lamination and forge-welding of alternate layers of uncarburized and carburized sheets proved to be a.spectacular and.useful Indian discovery made much before the era of laminated Egyptian knife dated 900-800 BC.<ref name=":1" />

 

 

The forging of wrought iron seems to have reached its zenith in India in the first millennium AD. The earliest large forging is the famous iron pillar with a height of over 7 m and weight of about 6 tons at New Delhi ascribed to Chandragupta Vikramaditya 400- 450 CE . The inscription of the Gupta period of the 4th century CE is in Brahmi script of Sanskrit (Figure 8).The pillar is believed to have been made by forging together a series of disc-shaped iron blooms. The Iron Pillar, the earliest and the largest surviving iron forging in the world, is regarded as a metallurgical marvel because it has defied the laws of corrosion of iron even after so many centuries, earning the nickname, the ‘rustless wonder’. Its astounding corrosion-resistance is partly due to its composition; high slag and phosphorus (0.25 p.c.) content and low manganese (0.05) and sulphur (0.005) content.<ref name=":1" /><ref name=":4" />

'''Iron Pillar of Delhi''' : The forging of wrought iron seems to have reached its zenith in India in the first millennium AD. The earliest large forging is the famous iron pillar with a height of over 7 m and weight of about 6 tons at New Delhi ascribed to Chandragupta Vikramaditya 400- 450 CE . The inscription of the Gupta period of the 4th century CE is in Brahmi script of Sanskrit (Figure 8).The pillar is believed to have been made by forging together a series of disc-shaped iron blooms. The Iron Pillar, the earliest and the largest surviving iron forging in the world, is regarded as a metallurgical marvel because it has defied the laws of corrosion of iron even after so many centuries, earning the nickname, the ‘rustless wonder’. Its astounding corrosion-resistance is partly due to its composition; high slag and phosphorus (0.25 p.c.) content and low manganese (0.05) and sulphur (0.005) content.<ref name=":1" /><ref name=":4" />

Another more recent product of repute is the high carbon steel manufactured in the past by the crucible process. Wootz is the anglicized version of ukku in the languages of the states of Karnataka, and Andhra Pradesh, a term denoting steel. Literary accounts suggest that steel from the southern part of the Indian subcontinent was exported to Europe, China, the Arab world and the Middle East. Studies on Wootz indicate that it was an ultra-high carbon steel with between 1-2% carbon and was used to make the fabled Damascus swords.

'''Wootz Steel''' : Another iron product of repute is the high carbon steel manufactured in the recent past by the crucible process. Wootz is the anglicized version of "ukku" in the languages of the states of Karnataka, and Andhra Pradesh, a term denoting steel. Literary accounts suggest that steel from the southern part of the Indian subcontinent was exported to Europe, China, the Arab world and the Middle East. Studies on Wootz indicate that it was an ultra-high carbon steel with between 1-2% carbon and was used to make the fabled Damascus swords.

* The Largest and Earliest Rustless Iron Forging Wonder : Iron Pillar of Chandragupta Vikramaditya at Delhi

* The Largest and Earliest Rustless Iron Forging Wonder : Iron Pillar of Chandragupta Vikramaditya at Delhi

* Wootz Steel prepared by indigenous crucible process.  

* Wootz Steel prepared by indigenous crucible process.  

* Monumental Iron pillars such as the one 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.

=== Zinc ===

=== Zinc ===