R. R. Angerstein
Reinhold Rücker Angerstein, born October 25, 1718 at Vikmanshyttan, died January 5, 1760 in Stockholm, was a Swedish metallurgist, civil servant and entrepreneur.[1]
See 'R R Angerstein's Illustrated Travel Diary 1753-1755: industry in England and Wales from a Swedish perspective'[2]