GUEST: I received it as part of an inheritance from an aunt who was the wife of a partner of Andrew Carnegie in Pittsburgh, Pennsylvania.

So... APPRAISER: So she had some nice things, I'm sure.

GUEST: She was a very elegant person.

I was drawn to it because it has so many different elements of it.

APPRAISER: When I looked at it the first time, what I was drawn to was the wonderful combination of colors.

I love that it has the step-cut jade, and then it's got diamonds, of course, and then it's got rock crystal.

This is fluted rock crystal, and wonderful accent of coral.

But what was strange about it is the outer rim, because it really doesn't make sense for it, because the center is clearly Art Deco... 9Mm-hmm.

...and the rim is sort of later, 1940s.

So I started to really examine it, and what do I see is, I see little, tiny numbers.

APPRAISER: And whenever we see that kind of numbering, we say, "Maybe this has a signature."

But it was very difficult to see.

Underneath these gold rings I was able to make out first, "made in France."

APPRAISER: And then on the other side, "made in France"-- who would have made this?

So I was hoping for a big name, and you know what?

I got a great name-- Van Cleef & Arpels.

Van Cleef & Arpels made this probably in the late '20s, and it was a dress clip.

GUEST: Mm-hmm, mm-hmm.

APPRAISER: Which you would just clip on.

And what happened with these dress clips is that over time, they were changed.

Either the mechanism came off or it just was out of fashion, because in the '40s, what happened is, yellow gold was fashionable.

GUEST: Mm-hmm.

APPRAISER: So what someone did was actually took a very ordinary yellow gold circle brooch and took it to a jeweler and they just stuck it on.

They didn't even pay attention... (chuckling): ...that it had this great signature...

GUEST: Amazing.

APPRAISER: ...and hid it!

GUEST: Amazing, yeah.

APPRAISER: Which today, what we would do is, take it off, try to put it back as a dress clip.

GUEST: Mm-hmm.

APPRAISER: But if you like the way it looks, you're probably just gonna leave it just the way it is.

GUEST: I wore it into a jeweler's shop one day in New Haven, Connecticut, and the jeweler said, "That's a beautiful brooch."

And he said, "It's very unusual.

I've never seen anything like it."

But that was the end of our conversation.

APPRAISER: That was, yeah.

The signature is a driving force.

This brooch, just the way it is, in its altered state...

GUEST: Mm-hmm.

APPRAISER: ...I would say, if you had to go to public auction, we'd estimate it $5,000 to $7,000.

GUEST: Wow, that's... APPRAISER: Which is great.

GUEST: ...extraordinary.

APPRAISER: If it was intact, probably $10,000 to $15,000.

GUEST: No kidding, yeah.

APPRAISER: So you've got a lot of value here.

GUEST: Thank you.