Operating earnings before taxes (EBT) were 40 million euros (35 million pounds) in the first quarter of its 2018/19 financial year to end-December, compared with 79 million euros a year earlier.

"Compared to the very strong first quarter of the previous year, unscheduled shutdowns at our Hamburg, Pirdop, and Luenen sites had a negative effect of approximately 25 million euros on earnings this year," the company said.

Aurubis repeated its forecast that full-year operating EBT will be "moderately lower" than in the previous year and that return on capital employed will be "slightly lower".

"We still see a good situation on our markets for the most part, and the impacts of our efficiency improvement programme will continue to unfold during the fiscal year," said CEO Juergen Schachler.

The company warned in December that maintenance shutdowns at its main plants could burden results in the new year.

"As a result, Aurubis recorded lower throughputs of both copper concentrates and recycling materials," it said on Wednesday.

"While refining charges for copper scrap were behind the very good levels of the prior-year quarter, they are still satisfactory at levels considerably above the long-term average."

Quarterly sales fell to 2.614 billion euros from 2.872 billion.

"The change compared to the prior-year quarter is primarily due to the significantly lower copper price and a production-related decline in precious metal sales," it said.

London copper fell almost 17 percent in 2018.

On the raw material markets, Aurubis expects good copper concentrate (ore) supply and "satisfactory" copper treatment and refining charges (TC/RCs) until the end of the fiscal year.

TC/RCs are fees paid by mines and other concentrate owners to copper smelters to refine ore into metal and are a key part of copper refiners' income.

Aurubis also expects a fundamentally stable copper scrap market. The current low metal prices could nevertheless lead to lower copper scrap supply and so lower refining charges, it said.

On the product markets, Aurubis expects "robust, high" demand for copper rod and shapes products. Reduced demand for flat rolled products from the automotive sector is being countered by growth momentum from other market sectors, it said.

(Reporting by Michael Hogan; Editing by Riham Alkousaa and Subhranshu Sahu)