(Repeats item issued earlier. The opinions expressed here are those of the author, a columnist for Reuters.)
By Clyde Russell
LAUNCESTON, Australia, March 20 (Reuters) - Just how worried should nickel markets be about the latest threats by Philippine President Rodrigo Duterte to stop all mining in the world's biggest exporter of the metal ore? Probably not too much.
The reason to be relatively sanguine about the prospects for nickel supply isn't that Duterte is unlikely to follow up on his latest threat, although he may not.
It's that even if he does, the market is likely to be able to cope with the loss of Philippine nickel ore, despite having to make some short-term adjustments.
In the latest twist to Duterte's ongoing battle with his country's miners, the bombastic and populist leader accused them of funding efforts to destabilise his government, and mooted a total ban on mining.
Duterte told a March 13 media briefing that he was looking at a total mining ban "and then we'll talk", referring to miners.
The Philippine leader has said his Southeast Asian nation can live without a mining industry, and in broad terms he is correct, with the sector contributing just 0.6 percent directly to gross domestic product in 2016, according to data from the government's Mines and Geosciences Bureau.
While mining will make a bigger overall contribution to the economy once the services it consumes and the employment it provides are factored in, it's likely true that the Philippines can live without a mining sector.
But can nickel markets live without the Philippines, particularly China, the destination of the bulk of the Philippines' exports of unrefined ore.
The short answer is most likely yes, with the experience of Indonesia's ban on its nickel ore exports in 2014 being instructive.
Indonesia banned the export of several unrefined metal ores in January 2014 in a bid to encourage miners and customers to invest in a domestic processing industry.
The price of benchmark nickel in London surged some 57 percent from early January in 2014 to May of that year, but then embarked on a downward trajectory, before recovering last year in line with a more general rally in commodity prices.
The reason for the price surge was the fear that the loss of Indonesian supplies would substantially tighten the nickel market, but the rally faltered once it become clear that Chinese nickel producers could access alternative suppliers.
One of the main alternatives was the Philippines, which ramped up its exports of nickel ore to China as Indonesia's dropped to zero by 2016.
But China has been buying less Philippine nickel ore in recent years, with purchases falling 5.9 percent in 2015 to 34.28 million tonnes and dwindling another 11 percent in 2016 to 30.53 million tonnes.
The Philippines still dominates China's imports of nickel ore, accounting for 95 percent of the total, but China is also buying less nickel ore overall, with total imports slipping 9 percent in 2016 to 32.1 million tonnes.
China is still getting all of the nickel it needs, simply by increasing the amount it buys in more refined forms.
Chinese customs classifies nickel imports into refined nickel and alloy, ores and concentrates, and ferronickel.
Imports of ferronickel surged 60 percent in 2016 from the prior year, with Indonesia storming back with a 250 percent increase to 747,097 tonnes, a 71 percent share.
It's worth noting that Indonesian ferronickel isn't actually the same as supplies from other countries, being less refined and having a lower concentrate of nickel, as can be seen by Chinese customs data that showed in December it was less than half the price of cargoes from New Caledonia, the second-biggest supplier.
What has effectively happened is that the Philippines initially replaced Indonesia in supplying nickel ores to top buyer China, but now China is increasingly turning to low quality Indonesian ferronickel.
This will have implications for the workings of Chinese nickel pig iron producers, but overall it seems that China is far from short of the metal used to make stainless steel and other corrosion-resistant alloys.
A further sign of comfort in the Chinese nickel market is that inventories monitored by the Shanghai Futures Exchange SNI-TOTAL-D are still at relatively high levels.
In the week ended March 13 nickel stocks were 80,795 tonnes, down from the peak in August last year of 111,359, but still well above the 43,708 recorded at the start of 2016.
It's also possible that Indonesia will resume exports of nickel ore after the government introduced new regulations that allow miners to export some unprocessed ore if they are using the capacity at their refineries.
While it's far from certain as to how much nickel ore Indonesia may export, an official at the mines ministry suggested last year it could be as much as 15 million tonnes in 2017, about a quarter of the amount the country shipped out in 2013, the year before the ban was imposed.
It's also about half of what the Philippines shipped to China last year.
If Indonesia does increase exports of nickel ore, while maintaining those of its low-grade ferronickel, the risk is that the market will be oversupplied, irrespective or whether the Philippines bans mining or not.
In some ways Indonesia and the Philippines have been playing an unwitting game of political tag when it comes to nickel markets, alternately tightening or boosting supply and altering the form in which nickel reaches China.
But the nickel market has shown it can cope with the inconsistent politics of Indonesia and the Philippines. (Editing by Richard Pullin)