We should probably investigate steel mills in Scotland
https://cfindlay17.wixsite.com/clydebridge/history-of-iron-and-steel-in-scotla

Lanarkshire Steel Co manufactured Siemens Martin open hearth process steel, but their logo didn't have the arrow.
Nor did the Steel Co. of Scotland
https://www.gracesguide.co.uk/Steel_Company_of_Scotland
but the logo did have SSCL

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