The rand, which has in recent weeks mainly been driven by offshore sentiment, traded at 16.5850 versus the dollar at 0620 GMT, 0.29pc firmer than its previous close.
At 0645 GMT the rand was 0.6pc weaker at 16.7000 per dollar from a close of 16.6000 overnight, halting a recovery that has seen the unit gain around 4pc this week.
The dollar weakened, as robust US data and fresh hopes for US fiscal stimulus had investors confident enough about economic recovery prospects to seek out riskier currencies.
At 0615 GMT the rand was 0.18pc firmer at 16.9100 per dollar, following a close of 16.9400 overnight in New York in low volume trade with local markets closed for a national holiday.
"The rand has recovered from its worst levels around 17.3000 posted last night, but the markets are likely to remain cautious ahead of the weekend," analysts at Nedbank wrote in a note.
At 0635 GMT, the rand traded at 16.7100 per dollar, 1.09pc weaker than its previous close and giving up gains made on Wednesday when it touched 16.3210, its strongest since March 16.