What Am I? Riddles

I’m white, perfect for cutting and grinding. For most animals I am a useful tool. What am I?

I’ve been argued on my colour. Without me you’ll die. So many attempts on your life use me, so make sure you have many of my “White” friends. What am I?

Keep doing me to avoid lens dryness. What am I?

Kids, elders and a monster love me, I’m mostly round and brown if you ask me. What am I?

Kings and queens may cling to power, and the jesters may have their call. I am the most common but I can rule them all. What am I?

Light me up for a sprinkle of gold. What am I?

Light me up in backyard gatherings. What am I?

Lighter than feather and softer than silk, yet the strongest man in the world cannot hold me for more than a few minutes. What am I?

Lighter than what I am made of. More of me is hidden than seen. What am I?

Lighter than what I’m made of, more of me is hidden than is seen. What am I?

Like a clock, I strike but at no specific time and after this follows a delayed aggressive chime. With my movements, you may say I’m precise as I don’t like to go to the same place twice. What am I?

Like a river I flow, and you’re happy I do in vain. There is no escaping from my course, without causing pain. What am I?

Look at me one way and I weigh a whole lot; turn me around and you’ll see that I am not. What am I?

Look at me. I can bring a smile to your face, a tear to your eye, or even a thought to your mind. But, I can’t be seen. What am I?