A painting by a famous South African artist, valued at between £700,000 and £1 million (R13.5 million – R19 million), has been discovered in London – being used as a notice board.

The UK’s Guardian first reported on the discovery of the painting, which is titled “Arab in Black’ by famed South African artist, Irma Stern.

According to the report, Hannah O’Leary, a specialist in South African art at Bonhams auction house, made the discovery while she was doing a valuation visit to the London flat.

The painting was originally sold at Auction in the late 50s to raise funds for Nelson Mandela and other ANC members’ legal bill as they faced the death penalty for treason.

The owner of the piece emigrated to the UK in the 70s, bringing the painting with them.

The Guardian reported that Stern’s artwork has been rising in value, and an auction in 2011 saw one of her works sell for £3.1 million – or just under R60 million in today’s money.

Stern was born in Schweitzer-Renecke, a small town in the Transvaal in 1894, and passed away in Cape Town in 1966, and is considered one of the country’s most recognised artists.

According to Bonhams, the freshly-discovered painting will be auctioned off in a South African Sale in September 2015.

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