LONDON (AP) _ A coin commemorating the 50th birthday of Prince Charles went on sale today, with some of the proceeds from special keepsake packages going to his charity, The Prince's Trust.

The cupro-nickel coin, legal tender worth 5 pounds ($8.50), bears a new portrait of Charles' mother, Queen Elizabeth II, with the prince and The Prince's Trust featured on the back.

It can be purchased at Britain's post offices at face value or in a keepsake package costing 9.95 pounds ($16.95). The keepsake package contains information about the coin's design, the work of The Prince's Trust and the life of Charles, whose birthday is Nov. 14.

The Royal Mint will donate 50 pence (85 cents) to the prince's charity from every keepsake package sold.