This is after mining union members and executives from the world's top platinum producers met to discuss a deal aimed at ending a crippling 13-week strike.
(READ MORE: S.Africa platinum talks resume in bid to end 3-month strike)
Producers such as [DATA IMP:Impala], [DATA AMS:Amplats] and [DATA LON:Lonmin] all gained around one per cent.
The Top-40 index was up 0.61 per cent to 43,711.36, close to a life record of 43,840.65 hit earlier this month. The All-share gained 0.58 per cent to 48,643.31, also close to the record high.
Volumes were thin after a long weekend to mark the Easter holiday and as investors reduced activity ahead of a general election on May 7.
"There's too much uncertainty at the moment, particularly with the mines and elections," said Ryan Woods, a trader at Independent Securities.
Around 70,000 platinum miners have been away from work for around three months, costing their employers 14.3 billion rand so far, according to an industry web site.
"Offshore investors are waiting to see how much it affects the platinum producers going forward. They've lost so much money already now," Woods said.
Trade was slow with about 147 million shares sold, with advancers outpacing decliners 157 to 156, according to preliminary bourse statistics.