* Q1 adj EPS C$0.25 v adj EPS C$0.48 year-ago
* Revenue up 0.5 pct to C$708.8 million on nickel output
* Copper sales, realized copper price fall
May 2 (Reuters) - First Quantum Minerals Ltd's quarterly operating profit slid 42 percent on lower average copper prices and sales volumes, the base metals miner said on Wednesday.
Adjusted to remove one-time items, profit in the first quarter, ended March 31, was C$119 million ($120.32 million), or 25 Canadian cents a share, compared with C$206.7 million, or 48 Canadian cents a share, in the first quarter of 2011.
Net earnings attributable to shareholders were C$1.3 billion, or C$2.82 a share. That compared with C$206.7 million, or 48 Canadian cents a share, in the year-before period.
First Quantum was awarded a $1.25 billion settlement in early March after a long-running dispute over the ownership of the Kolwezi project in the Democratic Republic of Congo.
Revenue rose slightly to C$708.8 million on new nickel output from the Ravensthorpe mine in Australia.
Copper production was down 12 percent to 65,869 tonnes compared with 74,888 tonnes in the year-earlier period, while copper sales fell 4 percent to 67,789 tonnes.
The average realized price per pound of copper fell to $3.67 from $4.23 in the first quarter of 2011, while costs per pound rose 38 percent to $1.59.
The Canadian miner expects to produce 270,000 tonnes to 290,000 tonnes of copper in 2012. With numerous development projects under way, it plans to spend $1.2 billion to $1.4 billion on development costs this year.
First Quantum owns mines in Australia, Zambia and Mauritania, along with development projects in Finland, Zambia and Peru.