Can you tell the difference between the work of an internationally renowned artist and a four-year-old girl? 

Eagle-eyed art fans will have their knowledge tested in a charity auction and could pick up exclusive designs by David Hockney or Tracey Emin for as little as 99p.

St Wilfrid’s Hospice is organising the Big Art Secret where the work of artists will appear anonymously alongside artwork from more than 500 others from all walks of life on auction website eBay.

Contributors include Prime Minister David Cameron, Ronnie Corbett and Greg Rusedski. Charity patron David Dimbleby has also contributed a postcard and used his contacts to get Hockney and Emin involved.

One-hundred-year-old former teacher Vera Shephard from the Cen- tral School of Arts and Crafts in London, and four-year-old Eva, from Eastbourne, will also have their work go under the electronic hammer.

The auction went live on eBay on Thursday during national Hospice Care Week.

Money raised from the sale will go towards Campaign Hospice Reach, which is looking to raise £5.3 million in two years to complete the development of a new 20-bed facility in Broadwater Way, Eastbourne.

The exclusive postcards will also be on display for a week at Towner Gallery in Eastbourne from today.

Works by Yorkshire-born artist Hockney go for as much as £5 million at auction, while a postcard submitted by Emin for a similar auction recently re-sold for £16,000.

St Wilfrid’s Hospice chief executive Kara Bishop said the sheer number of postcards donated was a heart-warming start to an exciting event.

Duncan Adams, the hospice’s marketing director, said: “Hockney’s work is described as ink and colour crayon and we don’t have many of them in the auction while Emin’s is in her trademark style so we’re hopeful people will be able to spot them.”