After China and Turkey, hundreds of metal casting units (also called foundries) in and around Kolkata, the country’s oldest, are looking now at Japan to source cutting-edge technology and learn eco-friendly techniques. Aikawa Iron Works, Chuo Malleable Iron, Handa Casting, Hoshino Casting, Itochuko, Niake Seiki, Nishioka Malleable Iron, Niwa Chuzo, Sintokogio and Toyota Motors are some such companies they…