Spot iridium, a minor platinum-group metal (PGM) used in chemicals and electronics, was last quoted at $300/320 an ounce on Friday, up some $50 from a week ago – the highest since July 2002.

Traders said end-user buying in a small market lifted prices that have risen some 82% in a year, according to MiningWeekly.

"The market is going up, and it is industrial demand. Unlike other metals, the influence of speculators is limited," a trader said.

Platinum is near record highs of $1,093 an ounce, while palladium has touched $348 an ounce, its best for over three years. Rhodium hit hit levels around $4,300 an ounce at the start of the week, the highest since 1991, but has since settled back at $4,000/4,100