Glossary · Trade
Jacot tool
A bench lathe attachment used to burnish and true balance-staff pivots.
Explanation
The Jacot tool is a bench attachment in which a balance staff is supported between runners while its pivots are burnished with a polished steel or sapphire burnisher. Burnishing hardens and smooths the pivot surface rather than cutting it. It is the classic tool for restoring worn pivots, requiring considerable skill.
In the object catalogue
Catalogued objects whose own source record mentions “Jacot tool”. The quoted line shows where; it is the seller’s or museum’s wording, not independent verification.
