China Is Quietly Throttling Germanium and Quartz Exports to Taiwan

China has begun quietly restricting and delaying exports to Taiwan of germanium- and quartz-based materials, along with certain permanent magnets, according to an exclusive Nikkei Asia report published August 20. The squeeze operates not through formal bans but through customs clearances that stretch from days into months — an administrative slow-walk that is already lengthening lead times for Taiwanese aerospace and optical suppliers, and that lands squarely on top of the supply chain feeding the world’s AI accelerator fabs.

What Nikkei Found

Several optical technology manufacturers have faced lengthy customs checks and delays in obtaining germanium- and quartz-based materials from Chinese suppliers since last year, sources told Nikkei. The bottlenecks have worsened through 2026.

“This is a problem for the entire industry,” an executive at an optical products company told the publication. “Many of my colleagues have faced the same issue, and it could significantly increase order fulfillment times in our business.” The executive said difficulties arose specifically when germanium- and quartz-based materials went through Chinese customs.

Perhaps more telling than the delays themselves is the pressure campaign behind them. “We were told that some of our Chinese suppliers were summoned by government officials and questioned about their customers and shipments,” one source said. That detail matters: it signals a deliberate, targeted policy rather than incidental congestion at ports — Beijing interrogating suppliers about who their Taiwanese customers are before shipments are released.

The head of a company that makes semiconductor manufacturing equipment told Nikkei that lead times for its products have increased by several months because of China’s quartz restrictions, affecting production overall. “The quality and precision requirements for quartz in the semiconductor industry are very strict, and at this time we have no alternative source of supply outside of China,” the executive explained.

On the aerospace side, certain permanent magnets — particularly neodymium magnets, which are critical for motors, including those used in modern robotics — have become a bottleneck. Finding cost-effective alternatives outside China is not easy, according to the head of an aerospace supplier.

Why This Matters for AI

At first glance, germanium and quartz look like niche industrial materials. They are anything but. Together they form the physical substrate of the AI economy’s connective tissue — the fiber, the optics, and the crucibles without which no accelerator fab runs.

Germanium is the dopant inside optical fiber. Every strand of fiber optic cable depends on germanium dioxide to raise the refractive index of its silica core, creating the total internal reflection that carries light across thousands of kilometers. Fiber optic applications consume roughly 30% of global germanium production, and telecommunications broadly accounts for 50–54% of worldwide consumption. A single GPU rack in an AI data center consumes an estimated 36 times more fiber than a traditional CPU rack, and the five largest hyperscalers plan to spend $660–690 billion on infrastructure in 2026. Germanium prices have already climbed roughly 200% since January 2024 — from about $2,839 per kilogram to $8,597 per kilogram in February 2026 — and optical fiber prices surged more than 70% in late 2025, according to an Introl supply-chain analysis.

Quartz is the crucible of chipmaking. High-purity quartz is essential for crucibles, wafer carriers, and optical components in semiconductor fabrication. The executive’s comment — “we have no alternative source of supply outside of China” — is the single most alarming line in the report, because it comes from a semiconductor equipment maker. If quartz components are delayed, fab tool shipments slip; if tools slip, capacity expansions slip.

Taiwan sits underneath all of it. The island’s fabs produce the overwhelming majority of the world’s most advanced AI accelerators, and its optical and aerospace suppliers are now reporting months-long delays in materials they previously received in days. Nikkei’s framing is precise: this is a new chokepoint layered above the already contested silicon supply chain.

A Pattern, Not an Accident

Beijing has form here. In late 2024, China’s Ministry of Commerce tightened export controls on dual-use goods including gallium, germanium and other materials, producing what analysts called a “severe shortage” of germanium on global markets. In early 2026, after remarks by Japanese Prime Minister Sanae Takaichi regarding Taiwan, China banned exports to Japan of dual-use goods with military applications. A CSIS analysis notes China has explicitly leveraged rare earth export restrictions against Japan in 2026 “to deter support for Taiwan.”

The Taiwan squeeze extends that playbook with a lower temperature and higher deniability. No ban has been announced. No ministry statement exists. Just customs officers taking their time, and suppliers being questioned about their customer lists. That makes it harder to protest, harder to retaliate against, and harder to date precisely — but no less real for the companies living through it.

It also lands amid a broader economic squeeze: tungsten prices have surged sixfold as US-China restrictions tighten supply, and 2027 memory capacity is reported as effectively sold out as buyers quietly lock in supply.

The Washington Collision

The timing is awkward in the extreme, because Washington is moving in the opposite direction on the same materials. On August 11, the FCC proposed an import ban on Chinese optical transceivers — the modules that let data travel at light speed between racks — precisely because China holds about 56% of the global market for them. The Trump administration is separately drafting restrictions on Chinese data center devices, per Reuters.

The result is a pincer: the United States wants to exclude Chinese optical hardware from its data centers, while China is restricting the raw materials needed to build optical supply chains anywhere — including in Taiwan, the American tech sector’s single most concentrated dependency. Analysts have warned that a transceiver ban could remove up to 60% of AI data center module supply from US markets before Western replacements (which themselves need Chinese indium and germanium) can scale. Meanwhile, fiber manufacturers are expanding capacity — Meta signed a $6 billion agreement with Corning — but new optical fiber preform capacity carries an 18–24 month lead time, meaning any supply gap persists through at least 2027.

What to Watch

Three indicators will tell us whether this escalates. First, whether TSMC and its equipment suppliers publicly acknowledge quartz-related delays in quarterly calls — so far the squeeze is felt upstream of the fabs. Second, whether the US–China germanium export truce (Beijing suspended its ban on germanium exports to the US until November 27, 2026) survives its expiry, since licensing controls and military end-user prohibitions remain in force regardless. Third, whether Taiwan’s government formally raises the customs delays in trade channels, which would convert a quiet squeeze into a documented dispute.

The deeper lesson is structural. The AI industry has spent two years mapping its exposure to advanced lithography and HBM memory. The Nikkei report shows the next chokepoints are one layer down — in dopants, crucibles, and magnets that cost a few thousand dollars per kilogram but without which the trillion-dollar stack above them does not function. China appears to have mapped those layers first, and is now demonstrating, quietly and deniably, that it knows exactly where the glass is thinnest.