Short answer
A replica Cartier Ballon Bleu 28 mm copies a quartz watch. The small Ballon Bleu measures 28.6 mm across, about 9.3 mm thick, runs on a battery, and carries a blue synthetic spinel in the crown. Most replicas match the outline. They miss on case thickness, the crown stone, dial print, and movement type.
Specs to compare
- Case diameter: 28.6 mm
- Case thickness: about 9.3 mm
- Movement: Cartier calibre 057, quartz
- Crystal: sapphire
- Crown: fluted, blue synthetic spinel cabochon
- Dial: silvered opaline, Roman numerals, blued steel sword hands
- Water resistance: 30 m
- Steel reference sample: W69010Z4
Cartier publishes these figures per reference. Gold 28 mm models and leather strap versions share the case size but differ in weight and finish. Numbers for those references were not checked here.
Checks that matter
Seconds hand
The 28 mm Ballon Bleu is quartz. The seconds hand jumps one step per second. A smooth sweep points to an automatic movement, which is the wrong movement for this size. Ask for a video with the seconds hand in frame.
Crown cabochon
The stone should be a blue synthetic spinel. Counterfeits use glass, resin, or plastic. Color drifts purple or pale. On the real watch the stone sits flush inside the fluted crown.
Case thickness
Calipers settle arguments. Extra depth comes from a thicker caseback and a spacer around the battery. A 0.5 mm to 1.5 mm gain changes how the watch sits under a cuff.
Dial and hands
Read the Cartier signature, the Swiss Made line at 6 o'clock, and the Roman numerals. Check that the crown lines up with 3 o'clock and the minute track sits level. Blued hands are steel, not paint. Loose print and a tilted track are common faults.
Caseback
Look for reference number, serial, and the 30 m marking. Engraving has depth and raised edges. Laser printing looks flat.
Bracelet and clasp
Inspect screw heads, link gaps, and clasp engraving. A steel bracelet should flex without rattle and the clasp should close with one firm click.
Questions for a seller
- Case diameter and thickness in millimeters, measured with calipers?
- Movement maker and model?
- Sapphire or mineral crystal?
- Cabochon material?
- Photos of the caseback and clasp?
- Return policy and shipping method?
Price and legal facts
Listings for the 28 mm replica run from about USD 60 to USD 400. Movement, crystal, and bracelet drive the price. In the US, 18 U.S.C. 2320 covers trafficking in counterfeit goods, and 19 U.S.C. 1526(e) lets Customs seize and destroy counterfeit shipments. Risk lands on sellers, importers, and shippers.
Unknowns
Exact reference numbers for gold 28 mm models and current service costs for Cartier quartz movements were not verified. Confirm those with Cartier or a watchmaker.