I would like to know the metals and alloys named in the Vedas and Itihasas(Ramayana & Mahabharatha) with special attention to mention of Iron. The general assumption is the Itihasas events could have happened in the Bronze age or earlier. What were the metals used in our ancient weaponry like swords, shields, arrows, etc as described in the earliest available sources?
Shrutis, Smritis and Itihasas mention name and use of metal many times. The metals mentioned are iron, silver, copper, gold, lead, brass, bronze etc.. But this doesn't mean that they were developed in latter times. They may be obtained through Vedic Yagyas or through Gods or through secret technology unknown now.
Metals in Shrutis:
Yajur Veda Taittariyea Samhita 4.7.5
May I for me the stone, clay, hills, mountains, sand, trees, gold, bronze, lead ,tin, iron, copper, fire, water, roots, plants, what grows on ploughed land, what grows.
Rig Veda 10.99.6
Lord of the dwelling, he subdued the demon who roared aloud, six-eyed and triple-headed. Trta, made stronger by the might he lent him, struck down the boar with shaft whose point was iron.
Rig Veda 10.101.8
Prepare the cow-stall, for there drink your heroes: stitch ye the coats of armour, wide and many. Make iron forts, secure from all assailants let not your pitcher leak: stay it securely.
Rig Veda 8.29.3
One brandishes in his hand an iron knife, firm, in his seat amid the Deities
Rig Veda 5.62.7
Adorned with gold, its columns are of iron. in heaven it glitters like a whip for horses; Or stablished on a field deep−spoiled and fruitful. So may we share the meath that loads your car−seat.
Rig Veda 1.121.9
Thou hurledst forth from heaven the iron missile, brought by the Skilful, from the sling of leather, When thou, O Much-invoked, assisting Kutsa with endless deadly darts didst compass Susna.
Grant, Son of Strength, thou rich in friends, a refuge without a flaw this day to us thy praisers. O Agni, Son of Strength, with forts of iron preserve thou from distress the man who lauds thee.
Rig Veda 4.37.4
Strong, with fair chains of gold and jaws of iron, ye have a splendid car and wellfed horses. Ye Sons of Strength, ye progeny of Indra, to you the best is offered to delight you.
Rig Veda 6.71.4
This Savitar the God, the golden−handed, Friend of the home, hath risen to meet the twilight. With cheeks of brass, with pleasant tongue, the Holy, he sends the worshipper rich gifts in plenty.
Atharva Veda 10.1.20
Swords of good brass are in our house: we know how many joints thou hast, O spell! Be sure to rise, go away from hence! O stranger, what seekest thou here?
Yajur Veda Taittareya Samhita 1.8.12
l Protect me in front, protect me at the side, protect me from behind; from the quarters protect me; from all deadly things protect me.
m Gold hued in the glowing of the dawns, Bronze pillared at the rising of the sun, O Varuna, O Mitra, mount your chariot seat, And thence behold ye Aditi and Diti.
There are so many other refrences too.
Metals in Itihasas
Valmiki Ramayan Yuddha Kanda 6.113.20
हिरण्यं वा सुवर्णं वा रत्नानि विविधानि च || राज्यं वा त्रिषु लोकेषु नैतदर्हति भाषितुम् |
"Neither silver, nor gold nor even diamonds nor the sovereignty of the three worlds, can be worthy of this message."
Valmiki Ramayan Yuddha Kanda 6.65.18
आददे निशितम् शूलं वेगाच्छत्रुनिबर्हणः |
सर्वकालायसम् दीप्तं तप्तकाञ्चनभूषणम् ||
Kumbhakarna, the annihilator of enemies, speedily took up a sharp spike fully made of iron, adorned with pure gold and splendidly shining.
Lord Krishnas Sudarshan Chakra also contained component of iron..
The Mahabharata, Book 1: Adi Parva: Khandava-daha Parva: Section CCXXVII
And Pavaka then gave unto Krishna a discus with an iron pole attached to a hole in the centre. And it was a fiery weapon and became his favourite. Having obtained that weapon, Krishna also became equal to the task.
Maces were mainly made by iron.
The Mahabharata, Book 3: Vana Parva: Indralokagamana Parva: Section LI
And amongst them will move that great warrior Bhima of terrible prowess, armed with his iron mace held on high and capable of slaying every hero. And high above the din will be heard the twang of the Gandiva loud as the thunder of heaven.
Arrows were mainly made by iron. But sometimes also made of steel, silver and copper.
The Mahabharata, Book 3: Vana Parva: Tirtha-yatra Parva: Section CLXXII
And battered and broken by the straight-coursing iron shafts, shot by me, the city of the Asuras, O king, fell to the earth. And they also, wounded by my iron arrows having the speed of the thunder, began, O monarch, to go about, being urged by destiny.
The Mahabharata, Book 4: Virata Parva: Go-harana Parva: Section LXII
And loud was the clatter made by Arjuna's shafts as they cleft the coats of mail belonging to mighty warriors, made of steel, silver, and copper. And the field was soon covered with the corpses of warriors mounted on elephants and horses, all mangled by the shafts of Partha of great impetuosity like unto sighing snakes.
Wheels of chariots were made up of iron:
The Mahabharata, Book 1: Adi Parva: Viduragamana Parva: Section CCIX
There were also large iron wheels planted on them. And with all these was that foremost of cities adorned. The streets were all wide and laid out excellently; and there was no fear in them of accident. And decked with innumerable mansions, the city became like unto Amaravati and came to be called Indraprastha (like unto Indra's city).
There are other many times where metals are used in Ramayan and Mahabharat
Metals in Smritis
Smritis mention frequent use of metals. Some of examples are:
SB 3.17.26. Moving about in the ocean for many, many years, the mighty Hiranyaksa smote the gigantic wind-tossed waves again and again with his iron mace and reached Vibhavari, the capital of Varuna.
SB10.41.20The Lord saw Mathura, with its tall gates and household entrances made of crystal, its immense archways and main doors of gold, its granaries and other storehouses of copper and brass, and its impregnable moats. Beautifying the city were pleasant gardens and parks. The main intersections were fashioned of gold, and there were mansions with private pleasure gardens, along with guildhalls and many other buildings.
Shiva Purana mentions Vishwakarma preparing Shiva Linga of Various metals.
Shiva Purana 2.14
All the deities, then prayed to lord Shiva, who after becoming pleased instructed 'Vishwakarma' to construct a Shivalinga for them. Vishwakarma then made a Shivalinga for Kuber, a Shivalinga of yellow diamond for Dharmaraj, a Shivalinga of dark coloured diamond for Varun, a Shivalinga of Indraned diamond for Vishnu and a goldden Shivalinga for Brahmaji. Similarly Vishwadeva was given a Shivalinga made up of silver, the Ashwini Kumars were given Shivalinga made up of bronze, Laxmi was given a Shivalinga made up of Crystal (Sphatik), Sun-god was given a Shivalinga made of copper and the moon was given a Shivalinga made of pearl.
Above are only a few refrences. There are much more use and mention of metals in Purans
Thus as a conclusion metals like iron, copper, silver, gold, brass, bronze etc. are used and mentioned frequently in our scriptures.
This a very good question. I would recommend that you read this humanities research paper: Minerals and Metals of India
It talks about the history of metals in India including Gold, Mercury, Copper, Lead, Zinc, Bronze, Tin, Diamond, Iron and Steel. More importantly, it uses references from Hindu texts to corroborate this history. I am not sure if any other research has been done on the mention of metals in Hindu texts. Here are some excerpts:
Early reference to gold is to be found in the Rig Veda Samhita. In all the sacrificial rites golden vessels were said to have been used.
The Arthasastra refers to gold having “the colour of lotus, soft, lustrous and not producing any type of sound”
Silappadikaram, the Tamil Classic by the prince Ilango Adigal, dated to the early Christian era is an epic that follows the twists of fate due the theft of golden anklets belonging to the heroine, Kannagi.
Some of the earliest literary references to the use of mercury distillation come from Indian treatises such as the Arthasastra of Kautilya.
The Rasaratnakara, a text ascribed to the great Indian scientist Nagarjuna, of the early Christian era describes this method of production of zinc.
Rasa Rasaratnasamuccaya, a 13th century text gives details of the distillation process by tiryakpatanayantra (distillation by descending). This ingenious method was devised of downward distillation of the zinc vapour formed after smelting zinc ore using specifically designed retorts with condensers and furnaces, so that the smelted zinc vapour could be drastically cooled down to get a melt that could solidify to zinc metal.
PS: I am not sure this will answer you exact question. Although, it might give you some relevant insights.