JOHANNESBURG—U.S. President Donald Trump’s pledge to rejuvenate the U.S. auto industry is threatened by China’s sudden thirst for platinum, a precious metal that’s largely irreplaceable in modern-day vehicle manufacturing, according to experts.
The risk to U.S. supplies of platinum is heightened by Washington’s fragile relations with South Africa, whose mines produce 80 percent of global platinum supplies, according to mining information service Africa Mining IQ.