This coin was issued as part of the 2017 Celebrating South Africa coin series, which celebrates milestones and symbols of South Africa’s freedom, democracy and culture.
The mint says:
"In 2017, the South African Mint introduced the theme of Celebrating South Africa. Fittingly, the same year marks the centenary of the birth, on 27 October 1917, of Oliver Reginald Tambo. This product series commemorates his legacy by depicting the roles he played at various stages of his life and political career in securing a free, democratic and culturally dynamic South Africa
"Comrade OR", as he was affectionately known, was a founding member of the African National Congress (ANC) Youth League and between 1944 and his untimely passing in 1993, took on various leadership roles in the party including General Secretary, National Chairperson, Deputy President and President.
Although "Comrade OR" did not fully experience the liberated and democratic dispensation we now enjoy, he spent the better part of his life standing up for those very ideals - for this, his legacy lives on.
The series consists of a 1 oz pure-gold R500 proof coin, a 1 oz sterling-silver R50 proof coin, a base-metal R50 non-circulating legal tender coin and R5 commemorative circulation coin.
The R50 OR Tambo base metal coin is the first non-circulating, collectable legal tender coin made from base metal." | 
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