Glossary · Mechanism
End-stone (cap jewel)
A flat jewel closing the end of a pivot hole, against which the pivot's end shake bears.
Explanation
An endstone (cap jewel) is the flat jewel against which the end of a pivot bears, paired with the hole jewel to control endshake and retain oil. Balance endstones sit within shock-protection springs in modern watches. Missing or cracked endstones cause increased friction and rapid pivot wear.
In the object catalogue
Catalogued objects whose own source record mentions “End-stone (cap jewel)”. The quoted line shows where; it is the seller’s or museum’s wording, not independent verification.
Pocket watch
Francis Bryant Adams 18k gold fusee and chain pocket watch
“This open-face pocket watch, dated circa 1850 and attributed to Francis Bryant Adams, Jr., features an 18k gold consular case made by casemaker William Francis. Measuring 41 mm …”
Movement
George Graham Watch Movement Mounted in a Brass Stand
“This pocket watch movement by George Graham of London, numbered 565 and dated by the auction source to circa 1735, is mounted within an ornate cast brass bezel and suspended in …”
Pocket watch
Omega Ref. 743.20 Pocket Chronometer
“This open-face, keyless-winding pocket chronometer is housed in an 18K yellow gold case. The watch features a white enamel dial with Arabic numerals and subsidiary seconds at 6 …”
Pocket watch
James Hornby Pocket Chronometer
“This 18k yellow gold pocket chronometer, created by James Hornby circa 1859-1860, is a half hunting-case, key-winding instrument measuring 49.8 mm. The case features engine-turn…”
Pocket watch
Lebet & Fils Hunting Cased Pocket Chronometer
“Movement contains a diamond end-stone”
Pocket watch
Adams & Son 18k Gold Key-Winding Chronometer Pocket Watch
“This 18k yellow gold hunting case pocket watch by Adams & Son of London, dating to 1852, is a key-winding chronometer. It measures 54 mm in diameter and weighs 147 grams. The wh…”