unknownsynthetic
evidence: unknown
no source states which grade this article was bought at — this row exists so 'unknown' stays countable instead of becoming an assumption
exec:frederic-piguet-21/unknown
accepteddisputed
movement
Frederic Piguet 21
bounding evidence — no range is drawn on the era axis
not after 1955
a dated example movement, ca. 1950 (+5 yr, the source says “circa”)“3) ca. 1950: L.U. Chopard & Cie, Geneve, Swiss, 17 Jewels”
not after 1965
a dated example movement, ca. 1960 (+5 yr, the source says “circa”)“1-2) ca. 1960: Bucherer, Swiss, 3 Adj, 17 Jewels”
Identity
A caliber is three separate things and this reference keeps them apart: the construction, the names it is sold under, and the article a brand actually bought. A watch model points at an execution — never at a bare construction — which is why “same caliber” is almost never a complete answer.
IDesign — the construction
Frederic Piguet 21
movementproducer: Frédéric Piguet SAarchive filing
IIDesignations — 0 names
No designation is recorded for this design yet.
IIIExecutions — 1 article
No source in this corpus states which grade any Frederic Piguet 21 was bought at. That unknown is stored as a real row rather than left blank, so it can be counted, filtered and excluded from any comparison that would otherwise assume parity.
Specifications
| Property | Value | Scope | Status | Sources |
|---|---|---|---|---|
Jewels build.jewel_count | 17 | — | accepted | |
Jewels build.jewel_count | 17 | Ranfft data sheet, the 17-jewel member of its 17/18 range | accepted | |
Jewels build.jewel_count | 18 | Ranfft data sheet, the 18-jewel member of its 17/18 range | accepted | |
Lift angle esc.lift_angle_deg | 53 deg | — | accepted | |
Casing diameter geom.casing_diameter_mm | 20.8 mm | — | staged | |
Movement diameter geom.diameter_mm | 20.4 mm | — | accepted | |
Movement height geom.height_mm | 1.73 mm | — | accepted | |
Movement height geom.height_mm | 1.75 mm | — | accepted | |
Swiss movement origin.swiss_movement | yes | — | accepted | |
Frequency osc.frequency_vph | 21600 vph | — | accepted | |
Frequency osc.frequency_vph | 18000 vph | — | accepted | |
Power reserve (typical) power.reserve_typical_h | 42 h | — | accepted | |
Introduced prod.intro_year | 1925 | — | staged | |
Hacking seconds wind.has_hacking_seconds | no | — | accepted | |
Winding mode wind.mode | manual | — | accepted |
Where a property carries more than one value, the values have different scopes — an official spec sheet and observed hardware, say. Different scopes are not a disagreement, so both are accepted and both are shown with the scope they apply to.
Lineage
The same relationships as the tree at the top of this page, with their sources. An absence in a column means no source stated one.
Ancestors · 0
Where this construction came from. Read up the arrows.
None recorded. An absence here means no source stated one, not that none exists.
Descendants · 6
What came from it — revisions, variants, clones, licensed copies.
- Blancpain 21 (Frederic Piguet 21)ébauche of
- Cartier 21 (Frederic Piguet 21)ébauche of
- Certina 20-10 (Frederic Piguet 21)ébauche of
- Longines 310 (Frederic Piguet 21)ébauche of
- Omega 700 (Frederic Piguet 21)ébauche of
- Zenith 53.5 (Frederic Piguet 21)ébauche of
Related · 0
Stored in a different table from descent. A successor is not a child.
None recorded. An absence here means no source stated one, not that none exists.
Sources
- 1Internet Archivehttps://web.archive.org/web/20230531190544/http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Frederic_Piguet_21archivetier 2retrieved 2023-05-3112 facts on this page
- 2Caliber Cornerhttps://calibercorner.com/frederic-piguet-caliber-21curated dbtier 2retrieved 2026-09-089 facts on this pagecited, never crawled
- 3Internet Archivehttps://web.archive.org/web/20200808233038/http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Blancpain_21archivetier 2retrieved 2020-08-081 fact on this page
- 4Internet Archivehttps://web.archive.org/web/20230906060831/http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Cartier_21&archivetier 2retrieved 2023-09-061 fact on this page
- 5Internet Archivehttps://web.archive.org/web/20181106121238/http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&a0&2uswk&Certina_20_10archivetier 2retrieved 2018-11-061 fact on this page
- 6Internet Archivehttps://web.archive.org/web/20171031000001/http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&142&2uswk&Longines_310archivetier 2retrieved 2017-10-311 fact on this page
- 7Internet Archivehttps://web.archive.org/web/20171031011326/http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&159&2uswk&Omega_700archivetier 2retrieved 2017-10-311 fact on this page
- 8Internet Archivehttps://web.archive.org/web/20230902014748/http://ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Zenith_53_5archivetier 2retrieved 2023-09-021 fact on this page