I am taken from a mine, and shut up in a wooden case, from which I am never released, and yet I am used by almost everybody.
Answer: pencil lead
When I am visible to you, you cannot see me, but when I am invisible, you long to see me. I am plenty with someone patient, but all the more scarce with a hasty one. I am greater than all, but still in the control of those who value my existence. Who am I?See answer
How many 9's are there between 1 and 100?See answer
Select a pack of riddles and try to solve it in an interesting way.
This riddle appears in the following downloadable PDF files: