An American numismatic expert labels this rippling the Orange Peel effect from heavily worn dies. See image below. Read more here: https://www.error-ref.com/orange-peel-texture/

Coin Type: Australia 1d Penny
Grade: aUNC
Year: 1953
Mint: Perth
Metal: Bronze
Mass (approx): 9.45g

For more information on Australian pre-decimal coins, see Top End Coin’s extensive library

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