The color blood red is a dark shade of the most common type of human skin pigment, meant to resemble what your would imagine when you think about an artery bursting with fresh warm liquid. The actual hue ranges from crimson (the deepest, richest Kamski-style crimson) down into shades that are more like wine or even brownish orange; this depends on how well oxygenated those fluids actually were at some point in time!