I don't know if you've been following Topaz lately, but there's a mine in Minas Gerais, Brazil that produces a Topaz that takes treatment better than any other Topaz in the world, and is the source of the newer, darker Swiss Blue Topaz.  We get our rough from this mine, have it cut and treated, and the results are evident in the pictures we've got for this ring.  This is an outstanding stone, and it is enjoying a new popularity Swiss Blue hasn't seen in years.  This stone is a gotta have!