Answer:
Sometimes it's silver but also gold. Printed on paper it's a treasure to hold. What is it?
What always comes into the house through the keyhole?
What cleans as it gets dirty only to get clean the more you use it?
MT_TF_S What are the missing letters? Why?
If it is absolute, it will corrupt absolutely.
All about, but cannot be seen, Can be captured, cannot be held, No throat, but can be heard. Who am I?