GUEST: I've sort of inherited it from my grandfather, who was a collector for 35 years. He probably acquired this clock sometime in the early '60s.

APPRAISER: This is called the wall model acorn clock. And there were several models that the J.C. Brown Company made of this acorn clock. They were all made, I think, in the 1840s and '50s. And this one I have always felt was the rarest one. Also, it was probably the one that was made the latest. The mantel acorn clocks were the earlier ones, and they looked quite different. When I first saw one of these acorn clocks as a young collector, I said, "That is the ugliest thing I've ever seen in my life." But since then, I think there's a haunting beauty about these things. When these clocks were made in the 1830s, '40s, and '50s, they were a very bold design for someone who was going to manufacture these clocks and try to sell them to an American audience. What an unusual design. Peter, when I first saw this clock, I thought that the veneer on this door had been removed and replaced. But looking at it further, I don't think so. It has a laminate on it of some sort, which is ebonized, and I believe that's original. One of the most interesting features of this clock is the label. It's got the original J.C. Brown label, who worked in Bristol, Connecticut, only about a half an hour's drive from where we are now, and the reverse painting does show some restorations here on the back, where it's been in-painted. The surfaces on the side have been varnished in an unattractive way, but that's the only real restoration I see to this clock. When we open the door to this, this is what I found inside: a note that says "rare, $2,500". I said, "Well, where did this come from?" and you told me...

GUEST: That was my grandfather's estimate of its value several years ago.

APPRAISER: Well, it's very rare, its condition is good, it's about $12,000 or $13,000 when you consider it's a greatly unrealized and undiscovered American antique.