Re: Ancient but not unchanged
Indeed. For one example, the oldest rocks known on Earth are zircons (actually small crystals), https://www.livescience.com/43584-earth-oldest-rock-jack-hills-zircon.html and even these date from over 100 million years after the earth was formed. The bit we stand on is literally the crust, inside it's very hot, and over time most things get cycled round and melted.
Biting the hand that feeds IT
