Launched by the South African Reserve Bank, the South African Mint Company and the Nelson Mandela Foundation in Houghton, the coin features a smiling portrait of the former president and Nobel Peace prize winner.

The father of the nation is shown wearing one of his signature patterned shirts on the coin's face, which differentiates his portrait from the portrayals of other former leaders on coins.

Showing appreciation during the unveiling, Mr Mandela said: “Today I am richer than yesterday.”

The new coin will share "Tata's" love, experience and leadership, Finance Minister Trevor Manuel said.

“We are so privileged to have Madiba with us; who actively continues to provide leadership and who continues to be an example to all of us. The coin is in celebration of your birthday but as a country we will be celebrating your life.”

The coin is a legal tender and should be used to purchase goods and services, said Reserve Bank Governor Tito Mboweni, who was also commenting during the launch.

"Do use it to buy goods and services and do not keep it at home," he said.

Five million of the coins have been minted and will go into circulation on 18 July as part of the many celebrations of Madiba’s 90th birthday.

Other initiatives in celebration of his birthday include a colouring book that will be unveiled soon.

A colouring in book, which will be published in time to commemorate the 90th birthday of Madiba, would give young children the opportunity to give their own colour to his life.

The 44-page Nelson Mandela Colouring Book will contain large drawings of the former president depicting interesting facts about his life from birth to the present.

It also has word and number games relevant to Mr Mandela’s life.

In other initiatives to mark the milestone birthday, a range of bangles featuring Mr Mandela’s prison number has gone on sale in an attempt to create jobs and contribute to the fight against HIV and AIDS.

A total of 45 artisans and workers are benefiting from the initiative, which is set to raise revenue for the 46664 campaign.

The bangles include 90 platinum and 24-carat gold versions.

About 8 000 of the bangles have already been sold worldwide.

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