The short answer
33671 is not a Cartier reference number. Cartier uses codes that start with W, such as W69012Z4 for the 42 mm steel Ballon Bleu de Cartier. The digits 33671 appear in marketplace titles, auction lots, and search queries, not in Cartier catalogs. A watch sold as a "Ballon Bleu 33671" is either a genuine piece with a wrong label or a copy. Ask the seller which Cartier W-code applies to the case and the movement.
What the genuine Ballon Bleu is
Cartier launched the Ballon Bleu de Cartier in 2007. The case is round with a domed profile. A fluted crown guard sits at 3 o'clock and holds a blue sapphire cabochon. The dial carries Roman numerals, a guilloché pattern, and blued steel sword hands. Sizes run from 28 mm to 44 mm. Movements include the quartz cal. 049, the automatic cal. 076, and the 1847 MC. Retail for the 42 mm steel automatic is about $7,000.
Where copies fail
- Cabochon. The genuine stone is faceted sapphire with visible depth. Copies use glass or synthetic spinel. The color reads flat under light.
- Crown guard. Genuine guards hold even flute spacing. Copy guards vary in flute count and depth.
- Dial. Genuine guilloché is cut on a rose engine. Copy dials are stamped, so the pattern looks printed at 10x magnification.
- Caseback. Genuine engraving is deep and crisp. Copy engraving is shallow and laser-etched.
- Weight. Cartier does not publish case weights. In the hand, a steel copy on a bracelet feels lighter because end links and the clasp are hollow.
- Movement. A quartz movement in a case sold as automatic is a copy. So is a rotor with no jewel bearings and a plastic movement ring.
Price bands
Copy Ballon Bleu watches sell in three bands. Entry copies run $40 to $90 and use quartz movements and mineral glass. Mid copies run $120 to $250 and add automatic movements and sapphire crystals. High-end copies run $300 to $600 and copy the case profile and bracelet more closely. No band reaches the $7,000 genuine retail figure.
Five checks in hand
- Hold the cabochon under a lamp. Genuine stone shows internal facets. Glass shows a single bright spot.
- Place a drop of water on the crystal. Sapphire beads. Mineral glass spreads.
- Wind and set the time. Copy crown threads feel rough and the stem has play.
- Open the caseback. Compare the movement number with the case number.
- Send the serial to a Cartier boutique or a paid authentication service for a written opinion.
Legal status in the US
Trafficking in counterfeit goods is a federal crime under 18 U.S.C. § 2320. A first offense carries up to 10 years; repeat offenses carry up to 20 years. U.S. Customs and Border Protection seizes counterfeit watches at ports of entry and can destroy them. Personal-use purchases carry different charges than resale, but the watch remains subject to seizure either way.
What is unknown
The origin of the number 33671 is not documented. No Cartier source lists it. No customs seizure record ties it to a specific factory. Treat any listing that uses it as a claim to verify, not a specification.