An exchange traded fund that tracks companies in the rare earth and strategic metals sector gained 3% on Friday following upbeat earnings from Molycorp (NYSE: MCP), a top holding.

Molycorp shares were up more than 10% after the company said it swung to a second-quarter profit while revenue rose.

“We are very pleased with our accomplishments this quarter, as we successfully completed two acquisitions that advance our vertically integrated mine-to-magnets strategy,” said Mark Smith, Molycorp chief executive, in the earnings release. “Global demand for rare earths remains very high, and supply outside of China continues to be tight.”

Molycorp is the third largest holding in Market Vectors Rare Earth/Strategic Metals ETF (NYSEArca: REMX), which climbed 2.7% on Friday. It holds assets of about $340 million.