Copper's momentum is building faster than most realize. With Oyu Tolgoi ramping up production, we're seeing one of the world's major miners shift its entire earnings structure—copper is no longer the sidekick, it's becoming the lead story.

Here's what's worth paying attention to: Rio Tinto's copper output is accelerating. The Oyu Tolgoi mine expansion is hitting stride, and that's material. Iron ore still bankrolls the operation with cash flow dominance, but copper's trajectory is undeniable. This matters because industrial metal supply dynamics feed into everything—inflation expectations, energy demand, construction cycles, you name it.

For traders watching macro cycles, copper scarcity signals matter. When major mining operations shift to higher-value metals like copper, it ripples through commodity indexes and affects how markets price growth bets. Supply tightness could persist longer than people expect if production ramp-ups don't keep pace with demand.

The play here: watch how copper prices respond if supply stays constrained. It's one of those under-the-radar indicators that moves bigger markets.