The 50 paise coin, commonly known as "Athanni," has been a significant part of India's currency system. Minted by the India Government Mint, the Mumbai (Bombay) Mint is one of the primary facilities responsible for producing these coins.

Identification of Mumbai Mint Coins:

Coins minted in Mumbai can be identified by specific mint marks:

• Standard Circulation Coins: Feature a small dot or diamond (♦) beneath the date.

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• Proof Issues: Display the letter 'B' beneath the date.

  Numista

Composition and Design:

Over the years, the 50 paise coin has undergone changes in composition and design:

• Early Issues (1957-1971): Composed of nickel, with a weight of 5 grams and a diameter of 24 mm.

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• Subsequent Issues (1972-1990): Transitioned to cupronickel.

• Later Issues (1988-2016): Minted in stainless steel, with a reduced weight of 2.9 grams and a diameter of 19 mm.

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The obverse side typically features the State Emblem of India with the country name, while the reverse displays the denomination and year of minting.

Collectible Variants:

Certain 50 paise coins from the Mumbai Mint are considered rare and are sought after by collectors:

• 1975 Proof Coin: Distinguished by the 'B' mint mark, indicating a Bombay proof issue.

  BidCurios

• 1979 Proof Coin: An extremely rare gem condition coin issued by the Mumbai Mint, notable for the 'B' mark.

  CoinBazzar

• 1978 Mumbai Mint Coin: Recognized as a rare collectible from the Mumbai Mint.

  Collector Bazar

Canteen Tokens:

In addition to official currency, the Mumbai Mint also produced tokens for internal use, such as the 50 paise canteen token. These tokens are rare and hold numismatic interest.

Current Status:

As of June 30, 2011, coins of denomination 25 paise and below were demonetized. The 50 paise coin remains legal tender but is rarely seen in circulation.