At 1500 GMT, the rand traded at 14.8400 against the dollar, 0.76% weaker than its previous close.
With the local economy remaining weak and facing power cuts, the rand had rallied on Monday mainly on the back of global factors, including higher commodity prices which benefit resource-rich South Africa.
But gold, platinum and palladium all fell back on Tuesday.
Eskom, which regularly enforces outages over faults at its coal-fired power stations that hold back economic growth in Africa's most industrialised nation, said it would extend rolling blackouts to Saturday.
In fixed income, the yield on the benchmark 2030 government bond was down 4.5 basis points to 9.51%.
Stocks rose, led by technology stocks and companies that derive much of their income abroad and benefit from weakness in the local currency.
Luxury goods maker Richemont, Sibanye Stillwater and tech investor Naspers were the three biggest climbers on the Johannesburg Top-40 index, gaining 2.69%, 2.57% and 2.26% respectively.
The Johannesburg All-Share index climbed 0.95% while the Top-40 rose 0.96%.
"The big thing is the rand that's weakening a bit that's good for commodities and as well as the earnings season in America that's given a boost to markets and that is overflowing into our markets as well," BP Bernstein portfolio manager Gerhard Parkin said.
A weaker rand helps mining companies who export gold in dollars.
Some stellar earnings reports have helped drive the Dow and the S&P 500 to record highs, lifting investor sentiment in October after concerns around inflation, the U.S. Fed's tapering and China Evergrande Group's crisis rattled markets last month. [MKTS/GLOB] [.N]
(Reporting by Olivia Kumwenda-Mtambo and Nqobile Dludla; Editing by Alison Williams)
