How do you identify a Seth Thomas clock?

To identify a Seth Thomas clock, check its movement for a maker's mark. You may need to remove the back of the clock to access it. During the 19th and mid-20th centuries, the clockmaker usually used its full name in script or block letters to mark its pieces. Later clocks are more likely to display either an S centered with a diamond or the initials ST positioned in a circle. If you have trouble finding a marking, a certified appraiser or knowledgeable antique dealer can perform the identification process for you. On 1stDibs, shop a collection of Seth Thomas clocks.