Market close: Donald Trump and Rio Tinto news dampens late trading

American President Donald Trump's newest ban and confirmation that Rio Tinto was not re-opening the fourth aluminium potline at Tiwai Point dampened late trading on the New Zealand sharemarket.

The S&P/NZX 50 Index fell 117.91 points or 1 per cent to 11,646.68 – its biggest fall of the week. Trading was again light and 38.7 million shares worth $139.53 million changed hands. There were 41 gainers and 88 decliners over the whole market..

Trump issued executive orders prohibiting transactions with the Chinese owners of smartphone apps TikTok and WeChat, taking effect on September 20.

Trump said the apps, developed and owned by companies in China, captured vast swathes of information from its users and the spread of them continued to threaten the national security, foreign policy, and economy of the United States.

There has been a flurry of activity in the energy sector this week. Rio Tinto closed the fourth of its potlines at the Tiwai Point aluminium smelter to cope with the restrictions caused by the Covid-19 lockdown and there was speculation that this would be re-opened.

The speculation came to nothing and then came suggestions that some electricity companies will soon be reducing their dividends.

Shane Solly, portfolio manager at Harbour Asset Management, said the Trump and Rio Tinto's moves, late in the day, took "a bit of the tone out of the market."

He said the gentailers gave back some of their recent gains, the Australian banks are under pressure because of the Melbourne lockdown, and there was profit-taking in Fisher and Paykel Healthcare and a2 Milk.

"All eyes next week are on those reporting latest earnings, Contact goes first on Monday," he said.

The energy stocks were up and down on heavy trading today. Mercury moved ahead 10c or 2.13 per cent to $4.80 with $1.7m worth of its shares changing hands, while Contact Energy was down 19c or 3.02 per cent to $6.10 on $9.1m worth of trading and Meridian fell 2c to $4.98 on trading worth $8.7m.

Fisher and Paykel Healthcare fell $1.04 or 2.85 per cent to $35.41 with $28.2m worth of its shares changing hands. The a2 Milk Company was down 33c or 1.58 per cent to $20.52 on $6.8m worth of trading. The trade in the two heavyweights made up about a quarter of the volume on the market today.

Westpac Bank fell 25c to $18.04 and ANZ slipped 5c to $19.05.

Dunedin-based Scott Technology, specialising in automation and robotics systems, reported it has been awarded a further multi-million dollar contract by Rio Tinto to provide equipment for a new sample preparation and analysis laboratory at the Robe Valley iron ore mine in Western Australia.

Scott was one the day's biggest gainers, climbing 10c or 5.88 per cent to $1.80. The other movers were Just Life – which announced increased profit – increasing 4c or 10.13 per cent to 43.5c, Cannasouth rising 2c or 3.77 per cent to 55c, and Pushpay Holdings lifting 20c or 2.56 per cent to $8.

Just Life Group, which supplies water coolers, announced an increase in unaudited profit before tax of $3.9m for the year ending June 30, compared with $2.6m last year. Its share price increased on only 21 trades worth $3859.

Wall Street had another good day, particularly the technology giants. The Dow Jones Industrial Index rose 185.46 points to 27,386.98, S&P 500 climbed 21.39 points to 3349.16 and the Nasdaq gained 109.67 or I per cent to 11,108.07.

Amongst the big technology stocks, Facebook was up 16.16 points or 6.49 per cent to US$265.28 ($397.54); Apple which is closing in on a US$2 trillion valuation rose $15.36 or 3.49 per cent to $455.61 and Adobe climbed 14.6 points or 3.25 per cent to $464.11. Google parent Alphabet, Microsoft, Amazon and Salesforce.com posted smaller gains.

At 5.30pm safe haven gold was trading at US$2058 an ounce but had fallen 11 per cent during the day, while silver was at $28.36 an oz.