From The Sieve:
No complete rocks have survived to tell of the formative years following Earth’s formation some 4.56 billion years ago. The material that would have existed at that time has been broken apart by the power of wind and water. It has melted and metamorphosed under the immense pressure and heat deep within Earth’s interior. It has been recycled back on to the surface. It has existed at every stage of the rock cycle many, many times over.