“It is We Who have sent down the Dhikr (The Quran) and surely, We will guard it (from corruption).” (15:9)
The heavier elements like Iron, Carbon, Sulphur, Gold, and others do not belong to Earth. Not only this, they do not even belong to our solar system as these elements could only produce inside the core of a star many times bigger than the size of our sun, Iron and most of the heavy elements on Earth came from the collapse of some star which exploded and threw out its material in space. Such a star is called super Nova, the death of a star and birth of something new. The blast usually is so powerful that it forces more heavy elements like gold, lead, platinum to produce. You may also independently confirm it by conducting a google search.
Indeed, We sent Our messengers with clear proofs, and with them We sent down the Scripture and the balance ˹of justice˺ so that people may administer justice. And We sent down iron with its great might, benefits for humanity, and means for Allah to prove who ˹is willing to˺ stand up for Him and His messengers without seeing Him. Surely Allah is All-Powerful, Almighty.