Calibre 23 — the 72's compact sibling

In brief

Few vintage Valjoux chronographs matter more than the 23. It shares a functional family with the 72 but comes in a different configuration, and brands that needed a dependable chronograph base without developing one of their own took it in quantity.

Short history

Nothing left Valjoux with a Valjoux name on it. Watch houses bought the 23 as a bare ébauche, then finished, decorated and regulated it to their own standard before it went anywhere near a case. That shared way of manufacturing explains why one calibre now appears in watches from firms that were direct competitors at the time.

Watches that used it

• Rolex (vintage chronographs)
• Heuer
• Universal Genève