I recently tried Hard Candy Beetle. It's a very fun duochrome glitter. Depending on the light, it changes from purple, to green, to gold.
Here you can see the gold to purple shift in the bottle. It was hard to get the lighting right to photograph the change on my nails.
This is a wonderful color! I received so many compliments on it. I would recommend putting it over a layer of black polish since it is a little thin. I used about 4 layers over bare nails. As you can see, I was also playing with my new dotting tools and rhinestones.