Minor metal prices continue to soar at the hands of China-induced supply constraints, sources said, with bismuth propelled to highs not seen since the first quarter and indium to nearly pre-recession levels.

Bismuth, which was trading below the $6-per-pound mark as recently as August, has skyrocketed to a range of $8.25 to $9.50, with some traders reporting small quantities exchanging hands at as high as $9.75 per pound.

"$8 per pound is a joke now—there's no way you'd find anything below $8," one European trader said.