Energy stocks were mixed Monday afternoon, with the NYSE Energy Sector Index down 0.1% and the State Street Energy Select Sector SPDR ETF (XLE) fractionally higher.

The Philadelphia Oil Service Sector Index increased 0.7%, and the Dow Jones US Utilities Index fell 1%.

Front-month West Texas Intermediate crude oil shed 0.7% to $68.24 a barrel, and the global benchmark Brent crude contract decreased 0.6% to $71.72 a barrel. Henry Hub natural gas futures rose 0.8% to $3.22 per 1 million BTU.

In corporate news, Eni (E) has agreed to acquire a 25% stake in EnergyX's Chilean unit Black Giant for $225 million. Black Giant is developing a lithium project near the Salar de Punta Negra in northern Chile, Eni said Monday. Eni shares were down 1.1%.