England recorded a sixth successive victory in the tournament thanks in the main to an utterly dominant first half, during which they displayed flair and control at both ends of the court.
England coach Tracey Neville named a strong starting line-up for the match, the result of which would decide who would contest which semi-final.
Her counterpart, Nora Plummer, elected to leave Erin Burger on the bench.
South Africa made the first error of the match, as the ball bounced out of play early on. England capitalised, as two goals from Helen Housby gave the Roses a 5-2 advantage.
England were clicking into gear early on, but by contrast South Africa suffered a huge blow when their influential centre, Bongiwe Msomi, limped off with a knock.
Harten and Housby looked in sumptuous form, and the partisan crowd lapped up the performance as a confident-looking England extended their lead out to 16-9.
There was still time for an increase in the noise levels in the first quarter though, as the irrepressible Harten delighted the Roses fans with a long-range effort that gave a 19-11 gloss to the scoreline.
The Roses were in danger of disappearing out of sight early in the second quarter, as Harten and Housby continued their own personal scoring battle. Harten overtook Housby to lead that contest 12-11, while South Africa were evidently missing the dynamism usually provided by Msomi.
Harten was flawless up until this point, whereas at the other end, Maryka Holtzhausen was finding that luck was deserting her, as another of her attempts bounced out.
The first blot on Harten’s copy book arrived late in the first half, but her clinical performance up until then helped England to a 31-20 lead at the break.
England continued to move the ball with confidence in the third quarter, and Housby was the first to register in the second half.
The Proteas surged back though, and were given renewed hope by an upping in their intensity and a couple of uncharacteristic England errors.
Harten restored England’s ten-goal cushion as the score moved out to 38-28, and the South African third-quarter revival was brought to an abrupt end as England finished the quarter with a flurry of Housby and Harten goals giving them a 43-30 advantage ahead of the final quarter.
For the fourth quarter, Sigrid Burger was brought in to lead the South African attack, but an early miss allowed the Roses to extend their lead to 46-33.
South Africa again came back fighting, and would win the final quarter by two – England’s first quarter-defeat in the tournament up until now – but Neville took the opportunity to switch her line-up around with the semi-final now firmly in mind.
Serena Guthrie and Jo Harten were among those rested, but Housby remained on for the full match and fittingly ended the England scoring, netting her 24th as the Roses ran out 58-47 winners.
The semi-final line-up is now complete: England will face New Zealand and South Africa take on holders Australia.
England’s Geva Mentor said:
“We weren’t too sure what to expect – obviously South Africa had a really good performance against Jamaica earlier in the week, but for us it was important that we focused on ourselves and started strong, and I thought we did that.
“We were really pleased with that performance and how it sets us up for the semi-final on Saturday.”