Hello. My favorite topic is blue because it's the color of my eyes and the sky. 
that is interesting. You may find it fascinating that blue is one of the three primary colors?
I do find that fascinating. Blue is also the color of our blood which is a rare fact. Or blood only turns red as a reaction to the exposure of oxygen. 
that is true. maybe it has something to do with color mixing the and the visual effects of a specific color combination.
Could very well be. That's about all I know of that category. What is your favorite part about the color blue?
well, I do know that color theory first appeared in the writings of leone battista Alberti