Silence is the answer
Rough and grey as rock, I am plain as plain can be, But hidden deep inside a great beauty, what am I?
Sometimes I am harder than a rock, other times I am almost weightless. Everyone wants me, but then gives me away. Some people have a lot, others have very little. I come in many different colors all over the world. What am I?
Guess me:
I can be smooth as silk when you touch me Yet hard as rock when you hit me I can be crystal clear Or dark as pitch I can be still and silent Or I can rumble and roar. What am I ?