LONDON — After 30 years of work, Britain's pound coin is ready for a makeover.

The Royal Mint announced plans Wednesday to replace the weighty flat piece with a 12-sided coin made with two separate metals. It resembles a "threepenny bit" — a coin that circulated in Britain from 1937-1971.

British officials say the new coin will be harder to fake — as many as 45 million, or 3 percent, of the pound coins now in circulation are said to be counterfeit.

The new coin, which will circulate beginning in 2017, will feature a portrait of Queen Elizabeth II or whoever the monarch is at the time.

Royal Mint chief executive Adam Lawrence says the goal is to "produce a pioneering new coin" that will boost confidence and cut fraud.