Kolkata, India-based Coal India Ltd. (CIL) suffered second consecutive quarterly decline in profit in the three months ended September 30, as higher costs eroded the miner's margins.

CIL, the world's biggest coal miner by production, on Wednesday announced that its net profit slipped marginally to Rs 30.5 billion in the July-September quarter, from Rs 30.8 billion in the corresponding quarter of the last financial year.

A group of analysts surveyed by Thomson Reuters had projectedan average profit of Rs 35.2 billion for the miner's three-month period under review.

Profit declined even as the company's net sales increased 5.8 per cent to Rs 154.1 billion.

Commenting on the quarterly results, Finance Director A. Chatterjee said, "The sponge iron industry is in the doldrums, construction industry and thus cement makers have been hit. This led to lower price realisation in e-auctions."

CUL Chairman S. Narsing Rao also attributed the decline in profit to a fall in realisation of sales through e-auction and hike in costs. In the quarter under review, the company sold 12.88 million tones of coal, as against 10.28 million tonnes in the year-ago period. But, the realisation per tonne of coal slipped by Rs 19 to Rs 1,418 per tonne.

CIL shares gained 0.1 per cent on Wednesday. The stock has suffered a loss of around 20 per cent in their market value so far this year.