Have you ever noticed that not all meteors you see falling are the same colour? Growing up in the dark countryside away from city lights, I saw them sometimes, and their colour occasionally seemed to be an unusual and striking shade. Other times entire meteor showers tend to be a certain colour (the Quadrantids, for instance, tend to be blue). The reason for this is all down to what chemical elements are found in the meteors.
I stumbled across this image from AccuWeather.com somewhere on the internet and thought it seemed pretty cool. It’s a handy little chart for determining what’s in a meteor based on its colour.
These look accurate to me. Incidentally, a flame test for Calcium shows a rich red colour, but in this case I’d assume that you don’t find Calcium without Magnesium, so you’d get purple. As for the oxygen/nitrogen meteors, I’d guess the colour is due to chemical compounds in the meteor breaking down. Atomic oxygen emits red light when it’s excited. Which is actually why aurorae are red after heavy solar storms, when charged particles from the sun are energetic enough to reach Earth’s inner atmosphere. There, they fragment oxygen atoms and make a red glow.
So now you can know a little bit more about what you’re seeing if ever you watch a meteor shower. Adds an extra dimension, I think…