Specifications
Edge: Reeded
Weight: 5.75 grams (actual weight is 5.69)
Diameter: 23 mm (actual diameter is 23.06)
Composition: Copper-nickel
Minted: Royal Mint (Tower Hill), London, United Kingdom (1810-1975)
Mintage: 139,047,000
Engraver: Manuel Marín Jimeno
More information at https://en.numista.com/catalogue/pieces781.html