#52 - Centenary of Royal Institute of Chemistry stamps, 1977 celebrating British Achievement in Chemistry.
Designed by Jerzy Karo, each stamp commemorates a different Nobel prize winning achievement from the last 100 years;
Steroids - Conformational Analysis (8 1/2p),
Vitamin C - synthesis (10p),
Starch - Chromatography (11p) and
Salt - Crystallography (13p).
I love the Steroids one with the overprinting and really bright colours - it's a great stamp.
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