Logic riddles with simple answers

Armored but not a knight, snapping but not a twig, and always at home, even on the move. What am I?

Had at work day and night, it counts the numbers over and over. Although it counts all its life, it never gets past twelve.

Think of a number. Double it. Add ten. Half it. Take away the number you started with. What is your number?

What kinds of stones are never found in the ocean?

I dig out tiny caves, and store gold and silver in them. I also build bridges of silver and make crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs my help, yet many people are afraid to let me help them. What am I?

Can you write number 45 using only the number 4?

You can easily touch me, but not see me. You can throw me out, but not away. What am I?

What is black when you buy it, red when you use it, and gray when you throw it away?

On the first day they cover one quarter of the total distance. The next day they cover one quarter of what is left. The following day they cover two fifths of the remainder and on the fourth day half of the remaining distance. The group now have 14 miles left, how many miles have they walked?

I have a face but no eyes, hands but no arms. What am I?