a) Romans used armour and cutlery made from Indian iron.
b) Indian metallurgist Nagarjuna wrote the book ‘Rasaratnakara’ in 9th century BC which explained the preparation of various metallic compounds, the extraction and purification of metals.
c) Indians were the first to develop the method of extracting zinc and using it in alloys.
d) The famous iron pillar at New Delhi near Qutab Minar constructed by Vikramadithya about 1600 years ago has withstood the action of weather.