Photographer: SeongJoon Cho/Bloomberg JPMorgan Chase & Co. and the US government are backing Korea Zinc Co.’s planned $7.4 billion smelter in Tennessee that will supply critical minerals essential for chip-making, defense and aerospace. Korea Zinc — one of the world’s largest processors of the metal — said Monday it will establish a foreign joint venture called Crucible JV LLC to oversee the project. The venture will be comprised of Korea Zinc, the US government, and other unnamed investors, the company ...