Wikipedia
Wootz steel
Wootz steel is a crucible steel characterized by a pattern of bands, which are formed by sheets of micro carbides within a tempered martensite or pearlite matrix in higher carbon steel, or by ferrite and pearlite banding in lower carbon steels. It is the pioneering steel alloy matrix developed in India in the sixth century BC and exported globally. It was also known in the ancient world by many different names including Wootz, Ukku, Hindwani and Seric Iron.
Usage examples of "wootz steel".
It had developed a lively merchant class that traded wootz steel ingots and finished weapons to Marshad for dianda, then shipped the dianda south to the city-states.