Mystic Lilac is a really popular color and I actually bought it a little while ago. I have read that it is now a hard to find. I'm not really sure why it's so popular, but to each his own. It is a pale lilac base with a hint of teal green shimmer.
Gunmetal is a steel blue shimmer, nearly a frost. It went on really well and I didn't have any issues with streaking.