Plunging nickel prices and the market woes of world mining giants have shaken the French territory of New Caledonia, a tropical archipelago in the Pacific that is hostage to the metal's fortunes.

Though best known for its stunning lagoon, pristine beaches and diverse wildlife, New Caledonia's economy actually relies heavily on nickel, discovered here in the 19th century.

The price of nickel -- essential to the manufacture of stainless steel -- has plunged 35 percent so far this year to a six-and-a-half year low of less than $10,000 (9,000 euros) a tonne.

A slowdown in economic growth in China, the world's biggest consumer of nickel, and stockpiles of the metal amounting to more than 450,000 tonnes, have depressed the market.

"We were already in a deteriorating situation when the crisis hit because every sector was in a slowdown. I think we are not far from zero economic growth," Catherine Wehbe, director of the employers' federation Medef in New Caledonia, told AFP.

The federation is calling for a cut in government spending and for New Caledonia's economy to be diversified, moving away from what it describes as an "all nickel" mentality.

The archipelago, which has an estimated one-quarter of the world's nickel reserves, fretted this week as market turmoil engulfed Anglo-Swiss mining giant Glencore, which owns 49 percent of the Koniambo Nickel smelter in the north of the territory.

Glencore shares plunged 29 percent in London on Monday but regained the losses later in the week after protesting that it has "no solvency issues". Its shares have nevertheless tumbled by about 70 percent this year.

Glencore has invested more than $7 billion in Koniambo Nickel, which has been troubled by technical difficulties as it seeks to ramp up production.

Though the complex is 51-percent owned by the Northern Province populated mostly by the indigenous Kanak people, Glencore provides 95 percent of the financing.

- 'We are all scared' -

On Monday, the head of Glencore's nickel unit, Kenny Ives, met with French overseas territory minister George Pau-Langevin. No details of the talks were released but speculation about Glencore's future in the project runs rife on the archipelago.

"We know they did not buy Koniambo to lose money," said Yann Vu Van Lang, union representative at the smelter. "Today, we are all scared."

New Caledonia's historic nickel producer SLN says it is losing about 12.5 million euros a month and shares in its Paris-headquartered parent company, mining group Eramet, have fallen 50 percent so far this year.

"It is a deep crisis. Today, 80 percent of nickel producers are losing money," said Daniel Katrawa, general secretary of SLN.

Brazilian multinational miner Vale warned in January that 2015 would be a decisive year for its smelter, which is increasing output in the south of the archipelago. Vale has invested more than $7 billion in the island but the commodities crash has squashed its ambitions to break even for now.

The group, its shares now at a 12-year low, will review all of its projects in November.

Private ore exporters, whose major customers are Japan and Australia, hope they will be able to keep going, so long as the crisis does not endure.

The exporters' key concern is the failure of local leaders to agree on a mining strategy.

"We have no visibility on what they want to do with us," said Xavier Gravelat, head of the ore exporters' syndicate.

The organisation wants to be able to export nickel ore freely to China, a route that has provoked controversy within the government, with some leaders fearing that selling ore to China would lead to selling the resource off too cheaply. A draft accord has been signed but is now bogged down in legal and political rows.

Further complicating the outlook, pro-independence Kanaks are calling for ore exports to be halted in 2019 unless they are destined for off-shore smelters in which the archipelago has an interest.