Yankuang Energy Group's (HKG:1171, SHA:600188) coal sales in the first quarter dropped 6.3% year on year to 32,020 kilotons from 34,180 kilotons, according to a Hong Kong Stock Exchange filing on Thursday.

It includes the sale of self-produced coal, which slid 1.7% year on year to 30,600 kilotons from 31,130 kilotons.

The Chinese coal mining company's year-on-year output of saleable coal jumped 6.3% to 36,800 kilotons from 34,630 kilotons, the filing said.

The company's Shanghai shares slipped over 1% in recent trade.