China has announced a full ban on sulfuric acid exports starting May 1, using it as a strategic weapon to choke global mining of copper, zinc and lead. Since silver is produced only as a by-product of these mines, the move is expected to create a severe worldwide silver shortage, pushing prices sharply higher and possibly back to ₹4 lakh levels. சீனா மே 1 முதல் சல்பியூரிக் அமில ஏற்றுமதியை முழுமையா