A quiet shift in chip materials is turning molybdenum into a hot commodity, good news for chipmakers looking to escape China's grip on tungsten.

• China controls roughly 80% of the world's tungsten and has tightened export limits, pushing prices sharply higher.
• Tungsten is hitting a physical wall as memory chips stack ever higher — the metal wiring inside gets too thin and resists current.
• TSMC, Samsung and SK Hynix are turning to molybdenum instead, which conducts better at tiny sizes; SK Hynix plans to use it in its next 375-layer flash memory.
• Molybdenum's share of flash memory production is set to jump from a sliver to about 30% by 2027, with the related equipment market heading toward billions of dollars a year.
• The catch: China also mines about 40% of the world's molybdenum and started restricting some military-grade molybdenum powder last year.

Outlook: South Korea's newly confirmed molybdenum deposit could loosen China's hold, but building a supply chain that does not run through Beijing will take years.