Might as well recycle the rhenium while we do so, so we do.

FORBES: The EU Wastes 99% of its High Tech Metals

Rhenium has two major uses: one is at concentrations of 2 or 3% in nickel cobalt alloys for jet engines.

FORBES: The EU Wastes 99% of its High Tech Metals

However, in view of its present high price, rhenium (used in highly fuel-efficient aircraft engines) is now recovered from scrap bimetallic catalysts used in the oil refining industry.

FORBES: Recycling Scrap Rare Metals Vital to Future Technologies