The short answer
Most replica Must de Cartier watches are copies of the Tank Must or the vintage Must de Cartier Vermeil. Both are small quartz dress watches. A decent copy runs about $80 to $250. Under $40 you get a plated brass case, a printed dial, and a generic quartz movement that quits within a year. Four things decide quality: the case metal, the crown cabochon, the dial printing, and the caseback stamping. And know this going in. Selling counterfeit watches is illegal in the United States, so most of these listings sit in a gray market with no warranty and no recourse.
What the real Must de Cartier actually is
The Must line started in the 1970s as Cartier's answer to a cheaper market. Those watches used vermeil, which means gold plating over sterling silver, instead of solid gold. Same Tank shape, same roman numerals, same blue cabochon, lower price. Cartier later revived the name with the steel Tank Must. So "Must de Cartier" covers two different things: a vintage vermeil watch from the 70s and 80s, and a current steel model. Replicas chase both, and the vintage one is harder to copy well because the case shape is more delicate.
Which models get copied most
- Tank Must in small and large, steel case, quartz
- Must de Cartier Vermeil, the vintage size around 20 to 23mm wide
- Must de Cartier two-tone, gold plating over steel
- Tank Louis Cartier, less often, because the softened rectangular proportions are hard to fake
Movement matters less than you think
The genuine watches are mostly quartz. That works in a replica's favor. A $15 Ronda 763 or a Seiko quartz movement keeps time as well as anything Cartier puts in the case. Ask the seller what is inside. Ronda, ETA 955, or Miyota are all fine answers. "High grade Swiss movement" with no name usually means a generic Chinese caliber. Automatic Tanks exist too, and copies of those tend to be thicker and heavier than the real reference.
Vermeil versus plated brass
This is where the money shows. Real vermeil has sterling silver underneath the gold, so it carries a heft and a warm tone. A cheap replica is brass with a thin gold wash that wears through at the lugs and the crown within months, leaving a yellow-gray patch. Mid-tier replicas use steel with thicker plating. That lasts longer but looks cooler and harder in the hand. If a seller cannot tell you the base metal, assume brass.
What to inspect in photos
- Crown cabochon. It should be a faceted blue dome, not a flat plastic dot. This is the single easiest tell.
- Dial printing. Roman numerals need crisp edges and even spacing. Thick or blurry numerals are a giveaway.
- Secret signature. On many Tanks, the word Cartier hides inside one of the numeral strokes. Few replicas render it cleanly.
- Caseback. Look for a model number, Swiss Made, and on vermeil pieces a 925 silver stamp plus a plating thickness mark.
- Proportions. Compare length-to-width against the real reference. Copies often run a millimeter or two too thick.
- Strap. Genuine pieces come on calf or alligator. Most replicas ship with a stiff synthetic strap that should be replaced on day one.
Price tiers, roughly
Under $50 buys a disposable watch with a light brass case. Around $80 to $150 you get steel or thicker plating, a real cabochon, and a named quartz movement. Above $200 the case geometry and dial printing get close, though the plating thickness and the strap quality still lag. None of these tiers match the weight of a vermeil case, and none hold value.
Legal and practical notes
Trafficking in counterfeit goods is illegal in the US and carries civil and criminal exposure, and Customs can seize shipments at the border. Buying a single piece for personal use is lower risk than selling, but it is not zero and it varies by country. Practically speaking, no replica can be serviced by Cartier, resale value is close to nothing, and the plating wears at the contact points. Worth knowing before you spend $200: a used genuine Must de Cartier Vermeil frequently sells in the low hundreds and holds its value, which is a real alternative if the look is what you want.