Mystic Fire Topaz - the color of oil on water, maybe? Peacock feathers? 

Whatever it is, it's amazing, and it looks good day or night..  It complements just about anything you want to wear.

Titanium is a naturally iridescent metal that is applied to the back of the stone.  The dominant colors are green and purple, with occasional flashes of yellow and red. 

Set in a simple, oval basket (but nice and heavy) that lets the Mystic Fire do it's thing, and is accented with a nice, well cut CZ.  A 20pt diamond accent is also available upon request.

The stone weighs in the neighborhood of 12 carats, and measures 16x12mm.  It is roughly the size of a nickel. The mounting is what you'd expect to find holding such a nice stone.