What's Beneath Our Feet

Bricks are such funny things. Why aren't they the same color instead of shades ranging from orangey red to dark dried blood (excuse the gory description) color? Also, how come they aren't smooth? Instead they have little crevices, broken corners, and they aren't placed neatly together. Instead there are gaps between them. It's something that really confused me as I walked around campus today. Because how do they even get the different colors or why do they make different colors and why aren't they perfect?