By Nicholas Bariyo

KAMPALA, Uganda--Zambia's copper production increased by 16% on year during the first half of 2014, driven by mine and smelter expansions, the Central Bank of Zambia said Wednesday.

Copper output increased to 559,117 metric tons in the first six months of the year, up from 480,892 tons during the same period a year earlier, as miners continue to deliver on investments pumped into the mining industry in recent years.

Copper mining is the mainstay of the Zambian economy and the country depends on copper exports for more than 70% of foreign revenue earnings.

"Available indicators of economic activity suggest that the government is on track in meeting its growth objective for 2014, estimated at 6.5%," the central bank said in a report.

Companies such as Glencore PLC, Brazil's Vale SA (VALE), Toronto-listed First Quantum Minerals Ltd.(FM.T) and London-listed Vedanta Resources PLC (VED.LN) invested around $6 billion in Zambia during the global commodities boom, which peaked in 2011.

But a surge in global copper output and worries about a potential slowdown in China, the world's largest consumer and importer pushed copper prices toward four-year lows earlier in the year.

Reduced foreign revenue earnings have hit Zambia's local currency, the Zambian Kwacha, forcing the central bank to sell up to $533 million in the foreign-exchange market to stabilize the unit since the start of the year.

Analysts say that Zambia, which last year lost its position as Africa's top copper miner to Congo for the first time since 1998, is likely to reclaim its position this year.

Copper miners in Congo are grappling with acute power outages, which have slowed mining output, Congo's Chamber of Mines said last month.

Write to Nicholas Bariyo at nicholas.bariyo@wsj.com

(END) Dow Jones Newswires

August 06, 2014 03:58 ET (07:58 GMT)

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