The attributes of gold influenced the mind and heart of Indians
The Rigveda refers to hiranya ( the oldest Sanskrit word for gold ), gold vessels, necklace, chariots decorated with gold , River Sindhu (Indus) containing gold, ayas - copper or copper alloys – used to make Vajrayudha of Indra made by the process of sinchan (casting), karshnayas - iron.
Atharvaveda mentions of rajata (silver), trapu (tin) and sisa (lead) have been mentioned. Kautalya mentions of silver refining using Choolas.
The Mahabharata refers to pipilika gold (powdery ants’ gold) - Heaps were presented to Yudhishthira during rajasuya yagna.
Arthashastra of Kautilya, says about gold refining crucible steel- vratta –WOOTZ Steel(UTSA- characteristic of oozing out of low melting point liquid phase when heated to moderate temperatures . Sir Joseph BanksPresident of the Royal Society, London 1794)
Rasaratnasamuchchaya - three types of ferrous materials, viz, munda ( wrought iron ), tiksna ( crucible steel ) and kanta ( alloy steel ).
Special wrought iron- kanta used to make the world famous Delhi Iron Pillar (hot forging of directly reduced sponge iron blocks )- erected in Delhi in the 5th Century AD by King Chandra Varman -not corroded till date.
Nagarjun’s Rasaratnakar (second Century AD) -the earliest documentary evidence for the cementation process for brass making and reduction-distillation process for zinc extraction - 12 Century industrial process for zinc extraction uncovered at Zawar near Udaipur
Manasollas, written in 1131 AD -information on fine quality metal image casting by madhuchchhishta vidhan (lost wax process) - The famous bronze dancing girl from Mohanjodaro .