ASX up 0.9pct at noon as miners gain

The mining and energy sectors were both up by just under two per cent at lunchtime. -AAP Image

The Australian share market has once again failed to crack a key resistance level that's been a sticking point all week.

The benchmark S&P/ASX 200 index jumped 91 points in the first 10 minutes of trading on Friday to reach 7,196, only to retreat. 

At noon the benchmark S&P/ASX 200 index was up 64 points to 7,169.6, a gain of 0.9 per cent. The broader All Ordinaries was up 65.4 points to 7,404.7.

Every day this week except Tuesday the ASX200 has come within 20 points of 7,200 and then dipped again, a pattern that City Index analyst Tony Sycamore says is starting to look like the unwinding of institutional player being long the ASX200 and short the S&P500 or the Nasdaq.

"Makes sense after a period of fantastic outperformance by the local market," he said.

Whatever the reason, nine of the 11 sectors of the ASX200 were higher on Friday and the index was on track for its best result all week.

The mining and energy sectors were the best performers, both up a little under two per cent. BHP had climbed 2.5 per cent to $43.67.

But Appen had given back most of Thursday's gains after Canadian tech conglomerate Telus International revoked its tentative $1.2 billion takeover offer rather than sign a non-disclosure agreement and conduct due diligence.

Telus didn't give Appen a reason for backing away from the offer.

Appen was down 21.4 per cent to $6.50.