Yorkshire and the Humber
Stainless steel was invented in 1913 by Harry Brearley of Sheffield, working for Firth Brown Steels (now called Sheffield Forgemasters). SAE 304 stainless steel is the most common stainless steel today, invented by Dr William Herbert Hatfield FRS in 1924 at Firth-Vickers known as Staybrite 18/8, a chromium-nickel steel. Many Swiss watches were mostly made out of Staybrite.
Outokumpu
Avesta Sheffield was acquired 2001 and consists of a stainless steel mill with melting shop, hot rolling for heavy plates, hot rolling for 2000 mm width coils by Steckel mill and cold rolling mills. Avesta developed special stainless steel grades, high-alloy austenitic and duplex grades, optimized for good formability, weldability and high corrosion resistance.
Avesta has a long history in steelmaking, as does Sheffield in the UK where stainless steel was invented.