Seth Thomas Green and Black Adamantine Mantel Clock, Made July 1906

I repaired this beautiful Seth Thomas Adamantine mantel clock. It has the date code 6019G (July 1906) on the bottom. The clock has black and green marbleized finish and four celluloid half-pillars. It is 11 1/2 inches tall and 17 1/8 inches wide (at the feet). The minute hand is 2 1/8 inches long. The beveled glass seems to be an unusual feature.

  • Back of the movement
  • Date code July 1906

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Job 7035. I polished the pivots, installed 14 bushings, replaced the cracked strike mainspring with a Timesavers 15959 3/4 by 0.016 by 120 inches, and tightened the click rivets. The original time mainspring is 0.0172 inch thick, and the original strike mainspring was also 0.0172 inch thick. The movement is labeled “4 1/2” on the back, and is the same as the No. 89 movement.

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  1. I have this clock with 3 columns. It’s in pristine condition and sounds beautiful when it chimes. I don’t know the $ value but it’s worth a million to me.

  2. Yes, it usual for an Adamantine to have a brass bell.

    Those Japanese cuckoo clocks are interesting, I see one every now and then.

  3. It had a brass bell? Or is that just the reflection of the brass movement?

    My latest puzzlement is a “Miken” brand cuckoo clock, product of Japan. Completely non-Regula movement, square in shape, and mounted at a 45 deg angle like a diamond. Finally figured it out.

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