Question: what was the first rock discoverd

Natasha Stephen answered on 18 Jun 2014:

We have absolutely no idea what the first rock was that was discovered! The oldest rocks that formed on Earth were forming as the planet was, over 4.6 billion years ago! We have discovered rocks on Earth that are older than 3.7 billion years and have fragments in rocks from space (meteorites) that are nearly 4.7 billion years old, but these have all been discovered more recently!

The first rocks to be actually discovered by people would have been by our early ancestors over 1 million years ago even though the rocks themselves are much, much older!