Shown here are two reds used by contemporary artists. The color on the left is vermilion straight from the tube on the top, mixed with a little white on the bottom.
The color on the right is a very modern pigment, cadmium red. As you can see, the vermilion has a slightly more subtle tone to it, whereas, the cadmium is very shockingly bright. To my eye, it is almost garish. I have used it in the past always feeling compelled to tone it down with a little green or umber or something. Many of the modern pigments have that same characteristic. They can be so powerfully tinted that they can take over a color mixture. This is the reason I find the earths and historical pigments so much more appealing. They are naturally beautiful as they come from the tube or as you mix them.