Quick answer

A fake Cartier Tank Must two-tone is judged on three things: the gold tone of the bezel and bracelet, the dial print, and the crown cabochon. Get those right and the watch reads as convincing at arm's length. Get them wrong and no movement upgrade saves it. The genuine large Tank Must two-tone measures 33.7 mm by 25.5 mm, runs on quartz, and pairs a steel case with an 18k yellow gold bezel.

What you need before you compare

  • A reference photo of the genuine Tank Must two-tone in the same size you plan to buy
  • Digital calipers
  • A 10x loupe
  • A kitchen scale that reads to 1 gram
  • Daylight or a 5000K lamp

Work in daylight. Warm indoor bulbs flatter gold plating and hide the gap between 18k yellow gold and a gold-tone PVD layer.

Step 1: Measure the case

  1. Close the calipers on the case at the widest point of the brancards and note the width.
  2. Measure from lug tip to lug tip for the length.
  3. Measure the case thickness across the caseback and crystal.
  4. Compare all three numbers to 33.7 mm, 25.5 mm, and 6.6 mm for the large model.

A replica that sits 1 mm off in any direction will wear wrong and the bezel proportions will look heavy.

Step 2: Read the gold tone

  1. Set the watch next to a known 18k yellow gold ring.
  2. Tilt both under the lamp and watch the highlight roll across the surfaces.
  3. Note the color where the bezel meets the steel case.
  4. Check the inner edges of the bracelet center links for wear or flaking.

Solid 18k yellow gold has a warm cast with a hint of green and holds a soft highlight. Gold plating reads brassy or orange and turns dull where light hits at an angle. Plating that flakes at link edges is the first failure point on a two-tone replica.

Step 3: Inspect the dial

  1. Look at the Roman numerals at 12 and 6 with the loupe.
  2. Trace the outer edge of each numeral for step or bleed.
  3. Check the secret signature inside the VII numeral.
  4. Confirm the hands line up with the printed minute track.

Genuine dials carry sharp black numerals with no bleed. Replica dials show thicker strokes, filled loops, and a secret signature that turns into a smudge. The silvered opaline finish should shift from white to gray as you rotate the watch. A flat white dial is a downgrade.

Step 4: Check the crown and cabochon

  1. Look at the cabochon shape from the side.
  2. Compare the blue tone to a photo of the genuine stone.
  3. Turn the crown a quarter turn and feel the thread.

The genuine cabochon is a smooth domed synthetic spinel in a deep blue. Cheap replicas use a flat plastic disc in a bright toy blue. The crown should turn with light resistance and sit flush against the case.

Step 5: Check the bracelet and clasp

  1. Flex the bracelet and listen for rattle.
  2. Check gap size between each link.
  3. Open the clasp and read the engraving.
  4. Confirm the deployant closes with one firm press.

Tight link tolerances and clean engraving separate a top tier replica from a budget one. Shallow stamped lettering and a clasp that needs two hands to close are both signs of a low grade build.

Step 6: Confirm the movement and caseback

  1. Look at the caseback screws and check they sit flush.
  2. Note whether the caseback is screw-down or snap-on.
  3. Ask which quartz caliber is inside.

The genuine watch uses a Cartier quartz caliber, so a sweeping second hand is wrong. A Ronda or Seiko quartz movement with a one-tick-per-second beat is the correct match. Snap-on casebacks and cross-threaded screws are the most common shortcut on replicas.

Grade scale

Budget replicas run near 7 mm thick with flat gold paint and a printed dial that smears. Mid tier fixes the case size and dial but uses light plating that wears through in months. Top tier replicas match the case dimensions, use a thicker gold layer or solid gold caps, and copy the dial print and crown threading. Ask the seller for the plating thickness in microns before you buy.