Stocks ticked up, led by buying coming back into Lonmin after it cut costs and boosted third quarter mining performance.
By 1500 GMT the rand had gained 0.86 percent to 12.9175, a touch softer than the session-best 12.8900, blowing past 13.00 technical resistance barrier last reached on June 29.
"The disappointing US inflation numbers and the mothballing of the mining charter, that momentum is still coming through today," said currency dealer at Treasury One Andre Botha.
On Friday, South Africa said it suspended the implementation of new mining laws, which include raising the level of shares black people should own in mining firms, pending a court ruling on a challenge lodged by the Chamber of Mines.
The announcement of the laws in mid-June saw the rand slide 2 percent and mining shares plunge, and prompted a warning from ratings agency Moody's that the new rules would deter investment, raise costs and diminish cashflow generation.
The rand has now advanced nearly 5 percent from a two-week low in the previous week, aided by calm in the local political situation and dimming speculation of more than one rate rise in the United States.
The lure of the rand as a carry trade has also been boosted by expectations that the central bank will again keep benchmark rates unchanged at the end of its policy meeting on Thursday.
On the bourse, the benchmark Top-40 index ticked up 0.4 percent to 47,499 points while the All-Share index rose 0.43 percent to 53,827 points.
Shares in Johannesburg stock exchange-listed Lonmin rose to its highest level in more than a month after buying came into the previously over sold platinum miner when it cut more costs and improved its mining performance in its third quarter.
"We know they haven't had a great year, they've been in a lot of trouble. That's more to do with investors being very short on the stock and I would suspect that there's a bit of a squeeze on short covering," Independent Securities trader Ryan Woods said.
Lonmin closed up 14.82 percent to 12.86 rand.
In fixed income, the yield for the benchmark government bond due in 2026 fell 5 basis points to 8.645 percent.