GUEST: I bought it at auction, got it home, and I noticed it had a lot of sparkle. It was sold to me as a cubic zirconia in silver. So it really had a lot of fire, so I got under a microscope and started noticing little symbols on the outside of the shank and did a little research into one of the marks: the dog head platinum, a French mark.

APPRAISER: And how did you do that research?

GUEST: Internet. I just typed in "dog's head hallmark," and that's what came up. It said that France started using the dog head hallmark in about 1912.

APPRAISER: And how much did you pay for it, do you remember?

GUEST: About $30.

APPRAISER: About $30, and how long ago was that?

GUEST: It was about two or three years ago.

APPRAISER: Okay, so it was the fact that there are marks on the shank that made you wonder if there may be more to the story.

GUEST: That's correct. I was wondering, well, why would someone put cubic zirconia in possibly a platinum setting?

APPRAISER: Very interesting, it's a very good question and you make a very good point that the setting actually can reveal something about the rest of the piece. We tested this and tested it again, and the reason it's confusing is that this is not one stone. Initially it looks like one stone with multi-facets. But then once you start looking more closely, you realize that there's a central stone. It's an unusual setting. There are small, trapezoidal stones in a step fashion set all around the central stone. And it builds up like one big, large stone, but the play of light is a little odd because it's multiple stones, not a single stone. We tested it, we looked at it, we put it under the loupe, we used the diamond tester just to be sure. But in fact, it does test as a diamond, not as CZ. What you have is a ring that looks like it's sort of eight to ten carats from the top as a diamond. In fact, in the center is a stone that's about 1.5--let's say a carat and a half--and a few more carats in the surrounding stones in a platinum mount. It's a style of ring that could be as early as 1920s, 1930s. Altogether, given the carat weight, in a retail setting, I would say a conservative selling price would be in the $25,000 to $30,000 price range.

GUEST: Amazing. Amazing. I am shocked and happy. This is great.