South African online auction site Bidorbuy has reported a huge surge in the value of Nelson Mandela memorabilia, as the anti-apartheid leader remains in hospital, reports the Sunday Times.

Mandela's is the most valuable living signature on the PFC40 Autograph Index, sharing the position with Fidel Castro

"Nelson Mandela-related items have always been popular on bidorbuy. Now that the whole nation is holding its breath over [his] health the interest in Mandela-themed items has soared," chief executive Jaco Jonker told the publication.

He also added that the search term "Mandela coins" climbed to fifth place in the site's most popular searches. Last week, around 550 commemorative Nelson Mandela coins were sold through the site.

This is a trend that is already being seen in the rest of the world, with Mandela's being the world's most valuable living signature in the PFC40 Autograph Index.

We are currently offering a signed photograph of Nelson Mandela for sale.