Cehabit wrote Gold, platinum and other metals precioius were sucked into the earth’s core molten iron quickly after our planet formed.

So where does all the materials for our jewelry come from?

According to high-precision measurements of two isotopes, or atomic variants, tungsten 4 billion in old rocks from Greenland published online today in Nature [summary adds a little more, the full version is paywalled if] Precious metal bearing meteorites hit the Earth around this time, the surface of the planet in a veneer containing gold, platinum, and other long after their native counterparts had disappeared in the nucleus of the planet.