The best way to save yourself the trouble of authenticating a Cartier watch is to buy it directly from Cartier or an authorised merchant. If you want to get one at a discount, then visit the retailer's website at Cartier.com to study the watch's designs to familiarise yourself with their style. Two of the timepiece's trademark characteristics are its use of Roman numerals and watch hands that are shaped like swords.
Balk at a low price. A genuine Cartier will start at around £1,950, depending on the style of the watch. Make sure that if you are purchasing a timepiece for a few hundred dollars that you aren't buying a high-end replica.
Check the spelling of the word "Cartier" and all other writing on the watch and its accompanying wrapping. Fake products often have incorrectly spelt text due to poor quality control and the items being replicated in regions where English isn't the primary language.
Examine the watch's craftsmanship. The piece should be well-made and durable. Look out for a casing or a watch face that's scratched or dull, broken parts, dirt, flimsy links, and a watch that's hard to wind.
Heft the watch in your hand. Cartier watches, like other luxury accessories, should have a solid weight to them since they are made with better materials.
Rub a few drops of water across the face of the watch. The face should be made with a sapphire-quality glass that will make water bead on the surface instead of smearing.
Locate the serial number. Your watch should have one; look for it on the back or on the side of the casing. It will be a nice engraved number, not one that's barely etched in the surface.
See if the winder (called the crown) has a cabochon stone in it. This tiny polished gemstone is one of the signature characteristics of a Cartier piece. Also, the stone should be firmly secured in a setting; it should not be glued on top of the crown.
Find the logo. A real Cartier will bear the logo of two "C"s sitting back to back. The insignia will be on the back of the watch, on the watch's buckle and on the dial.
Ask if the watch is supposed to glow in the dark. If the merchant says yes, shine a flashlight on the watch for 10 minutes, then step into a closet and shut the door. The watch's face should glow brightly and the numbers should be easy to read. Cheap watches will use luminous elements of poor quality in an attempt to make the face glow.