The benchmark JSE Top40 index closed 0.08 percent down at 45735.57 points, while the broader all share index weakened 0.09 percent to 52496.62 points.
As the rand strengthened, investors sold off shares in local companies that earn the bulk of their revenues in hard currency, known as rand hedge shares, dragging the index lower.
“Rand hedge shares are a bit lower, it’s the combination of the slightly lower gold price and the rand strength,” said Cratos Capital equities trader, Greg Davies.
BHP Billiton declined 0.36 percent to R203.77, Richemont dropped 0.45 percent to R104.44, while Mediclinic International declined 0.77 percent to close at R122.97.
Gold shares also weakened as the bullion price came under pressure, with markets awaiting the outcome of the looming French presidential election.
Harmony Gold was down 5.02 percent to R31.42, while Sibanye Gold dropped 4.29 percent to R29.86.
Meanwhile, Wall Street was higher in early afternoon trading, boosted largely by gains in financial and materials stocks. The Dow Jones industrial average was at 20474.95 points.