Solid Gold castings of the hands of South Africa’s first black President Nelson Mandela have been sold for $10m (£7m) in bitcoin.

The castings of the late former South African president’s hand, palm and fist are believed to be the only ones left in the world.

Canadian crypto-currency exchange firm Arbitrade bought four casts from South African businessman Malcolm Duncan, according to a report by BBC Africa.

The firm said it planned to launch a global “Golden Hands of Nelson Mandela” tour to educate young people about the anti-apartheid icon’s life.

This is the first time artefacts of Mr Mandela have been sold in bitcoin.

Mr Mandela was jailed for 27 years for fighting white minority rule in South Africa.

He was released in 1990, and served as president from 1994 to 1999.

Mandela died in 2013 at the age of 95. He had turned into a global brand, with businessmen and artists cashing in on his name.

Mr Duncan, who now lives in Canada, bought the casts from mining group Harmony Gold in 2002 for about $31,000.

Half of the money paid to Harmony Gold was meant to go to charity, but it remains unclear as to whether that happened, Bloomberg news agency reports.

Harmony said it had “supplied Mr Duncan with the necessary paperwork verifying the provenance as requested by his attorneys,” but declined to comment on what happened to the donation, Bloomberg reports.