Old-style round pound coins are no longer legal tender, but anyone who has found one down the back of the sofa can still put it to good use by donating it to Twycross Zoo.
The conservation park is appealing for old legal tender to be donated to help safeguard the most endangered species on the planet.
Donations will go towards funding global breeding programmes for endangered species and contribute to conservation projects working all over the world.
Twycross Zoo is a registered charity which exists to support the conservation, education and research of some of the most endangered species on the planet.
The zoo is home to 153 different species, including many which are classified as endangered or critically endangered such as Amur leopards, the world's rarest big cat, whose numbers in the wild are dwindling due to habitat loss, increasing prey scarcity, disease and poaching.
Bornean orangutans are also cared for at the zoo; their wild relatives are threatened by illegal hunting and habitat loss due to the expansion of palm oil plantations.
There is a special donation station located in the Himalaya Centre which is also home to restaurants and cafes, all boasting a view of Twycross' rare snow leopards. Zoo bosses say any donations would be much appreciated.
Old pound coins ceased to become legal tender on 11.59pm on Sunday, October 15.
Shops are no longer able to hand out the old coins as change and the vast majority will refuse to accept them as payment.
Twycross Zoo is open to the public from 10am to 5pm daily, with the Himalaya Centre now open until 9pm on Fridays, but is closed on Christmas Day.
For more information or to book tickets, visit www.twycrosszoo.org or call 0844 474 1777.