REPUBLIC INDIA - One Rupee Error Coin - 1986 - Kolkata Mint - Copper-Nickel 1 Rupee (Struck on a 50 Paise Planchet) - 5.01 g

REPUBLIC INDIA: One Rupee Error Coin, 1986, Kolkata Mint, Copper-Nickel 1 Rupee (Struck on a 50 Paise Planchet), 5.01 g.

Error coins of this magnitude are highly coveted by numismatists specializing in mint errors. A "Rupee on a 50 Paise flan" is a spectacular visual error where a larger denomination's design is compressed onto a smaller metallic canvas. The 1986 Calcutta Mint strike is particularly interesting as the discrepancy in size (26 mm vs 24 mm) and weight (6g vs 5g) is immediately apparent to the touch. Genuine wrong planchet errors from this era are rare, as they typically indicate a breach in the standard minting protocol.