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Urban Jurgensen

Reference 2340 Tourbillon

Ref. 2340
2012–present · 42mm · caliber Urban Jurgensen Cal. 9: manual-wind with tourbillon, 21,600bph; flying tourbillon at 6 o'clock; movement hand-finished to the same standard as Cal. 11; one of the rarest independent tourbillons produced today
Mass-produced

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Movement tier: unclassified · caliber Urban Jurgensen Cal. 9: manual-wind with tourbillon, 21,600bph; flying tourbillon at 6 o'clock; movement hand-finished to the same standard as Cal. 11; one of the rarest independent tourbillons produced today
Medium-large: suits wrists 6.5 in+ (16.5 cm+)
42 mm case. Wears confidently on average to larger wrists. May overhang on slender builds.

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Authentication

The Urban Jurgensen 2340 Tourbillon is one of the rarest independent tourbillons produced today. Authentication requires examination of the flying tourbillon at 6 o'clock, provenance documentation, and ideally inspection by a specialist with direct UJ tourbillon experience.

Known issues in the market
  • Production is extremely small; any example should have clear and documented ownership history.
  • The flying tourbillon cage should complete one revolution per minute; this is observable and should be checked.
  • Provenance documentation from Urban Jurgensen is available for legitimate examples; a boutique can confirm a serial number.
AreaWhat to checkWhat is correctRed flag
movementFlying tourbillon rotation at 6 o'clockTourbillon cage completes exactly one revolution per minute; the motion is smooth and consistent; the bridge holding the cage is a single cantilever (flying design, no upper jewel)Tourbillon stopped or irregular; visible upper jewel or bridge above the cage (non-flying design); rotation rate other than one per minute
movementHand-finishing matching Cal. 9 specificationSame anglage, perlage, and straight-grained finishing as other UJ calibers; the tourbillon cage itself should be chamfered and polishedMachine-regular finishing on the cage or bridges; unfinished edges anywhere in the visible movement
dialDial construction and tourbillon apertureTourbillon aperture is positioned at 6 o'clock with clean, polished edges; dial text and numeral quality consistent with UJ standardsAperture edges that are rough or irregular; dial text quality below the standard of other UJ dials
caseCase metal and hallmarksPlatinum or gold with correct purity marks; 42mm case diameter; appropriately heavy for declared metalMissing hallmarks; weight inconsistent with declared metal
Common legitimate replacements
  • No standard replacement parts exist for the 2340 Tourbillon; any modification should be documented.
Expert resources: Urban Jurgensen boutiques can verify via serial number for this reference. Auction house specialists with tourbillon watch experience are strongly advisable for any purchase. Budget for a specialist inspection before any acquisition of this value.

Authentication guide

Last reviewed June 2026

The Urban Jürgensen 2340 Tourbillon is the complication centerpiece of the line. The tourbillon carriage, movement finishing, and provenance documentation are the primary authentication anchors.

Known reproduction risks

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LOW

No known reproduction at this production level

  • Generic tourbillon carriage design differs from UJ's proprietary cage
  • Finishing below the UJ standard

For the 2340, provenance documentation through Urban Jürgensen and major auction records is the definitive path alongside physical inspection.

Dial variants by era

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EraDescriptionIdentifiers
2340 Tourbillon productionTourbillon visible through dial aperture. Dial layout designed around the tourbillon carriage at the typical 6 o'clock position.
  • Tourbillon carriage at 6 o'clock, rotating once per minute
  • UJ movement architecture visible through the caseback or dial aperture
  • Precious metal case markings

Service part flags

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Tourbillon carriage

Original: UJ tourbillon carriage; the architecture and finish are consistent with the brand's hand-finishing standard.

Replacement tells
  • Carriage rotation rate other than one revolution per minute
  • Cage design inconsistent with UJ reference images
  • Any machine-finished bridges or rounded anglage on the cage
Movement finishing

Original: Same hand-finishing standard as all UJ calibers.

Replacement tells
  • Rounded anglage anywhere on the movement
  • Hazy or matte surfaces on bridges that should be mirror-polished

Case back markings

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All 2340 production
  • Urban Jürgensen markings
  • Tourbillon caliber designation
  • Serial number
  • Precious metal purity marking

Movement tells

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  • Tourbillon carriage should rotate once per minute; confirm over 60 seconds of observation.
  • Movement is manual-wind; no rotor present or audible.
  • Full UJ hand-finishing standard applies to every visible surface.
Sources: Urban Jürgensen official.

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