The all share was off 0.13% to 53‚983.20 points, with the blue-chip top 40 shaving off 0.1%.
Resources, which remain the best-performing sector in this second quarter, fell 1.38% amid some profit-taking in counters such Kumba Iron Ore.
Commodity prices were broadly higher, with the gold price pushing to multi-week highs amid a materially weaker dollar environment. The gold spot price fetched $1,218.37 per ounce.
Europe’s leading share markets were relatively flat at midday while US stock futures pointed to a firmer opening on Wall Street later in the day.
"Trading action in the bond market remains the dominant driver of near-term adjustments in risk assets for the moment," Imara SP Reid wrote in a note.
On the agenda this afternoon will be the release of the US producer price index for April following the disappointing US retail sales on Wednesday.
Among some individual shares on the JSE‚ Anglo American dropped 1.94% to R206.10.
Kumba Iron Ore was down 4.23% at R157.73 and Exxaro lost 3.52% to R91.69.
Imperial was off 1.34% to R189.42 while Harmony Gold gave up 2.27% to R20.71.
