Quick answer
A fake Audemars Piguet Royal Oak in rose gold is a copy watch. In most cases the case and the bracelet are 316L stainless steel with a gold plating 3 to 20 microns thick. The gold sits on the surface. An XRF scan at a jeweler reads that layer, not the metal below. A smaller group of copies uses solid 18k gold. Those sell for $8,000 to $20,000 and are still counterfeits. A third group uses tungsten alloy. Tungsten has a density of about 19 g/cm3, so a tungsten copy can match the heft of a gold watch. Tungsten copies are more common in Rolex models than in Royal Oak.
Genuine specs to compare against
Audemars Piguet builds the Royal Oak in 18k pink gold. Reference 15500OR.OO.1220OR.01 has a 41 mm case and runs the calibre 4302. Reference 15202OR has a 39 mm case, an 8.1 mm thickness, and the calibre 2121. The 26240OR chronograph uses the calibre 4401. The case back carries the Au750 stamp. That mark means 750 parts gold per 1,000, or 75 percent by weight. The balance is copper plus a small amount of silver. Copper gives the pink tone.
Density and weight
18k pink gold has a density near 15 g/cm3. 316L steel is 7.9 g/cm3. A gold Royal Oak on a full bracelet is heavier than the same reference in steel, but the movement, the sapphire, and the dial do not change, so the gap is smaller than the raw density ratio suggests. Weight alone is a weak test. Tungsten copies land in the same range. A water displacement test on a removed bracelet link gives a number a jeweler can use.
Case back and markings
- Genuine: Au750 plus a Swiss hallmark, plus the reference and the serial, cut by laser. Lines are thin and even.
- Replica: stamps run deeper and wider. Font shapes drift. Serial numbers repeat across batches.
- Genuine rotor: engraved family crest, straight graining, beveled edges. Copy rotors show curved grain and a stamped crest.
Bezel, dial, and bracelet
The octagonal bezel holds eight hexagonal screws. Each head carries one slot. Slot alignment changes between references and production years, so it is a weak test. The Grande Tapisserie dial has raised squares cut by machine. On copies the squares are shallow, the edges are soft, and the print spreads. The Swiss Made mark sits at 6 o'clock. The applied AP logo at 12 o'clock has polished edges on genuine dials. On the bracelet, the link edges are beveled and then polished. Copies show rounded edges and a wide gap at the clasp.
Movement checks
- Calibre 4302: 4 Hz, 70-hour power reserve, date. Base calibre of the 15500.
- Calibre 2121: 4 Hz, 40-hour power reserve. Base calibre of the 15202.
- Calibre 4401: integrated chronograph, 70-hour power reserve.
- Common copy movements: Miyota 9015, ETA 2824 clones, Seagull ST21, and 3135 clones. Signs include rotor noise, coarse finishing, and a date font that does not match the reference.
Price ranges
- Genuine 41 mm Royal Oak in 18k pink gold: above $50,000 at retail. Secondary prices move with the market.
- Plated steel copy: $200 to $1,000.
- Solid 18k gold copy: $8,000 to $20,000.
- Tungsten copy with gold plating: $500 to $1,500.
Tests that do not work
- A magnet. 18k gold and 316L steel are both non-magnetic.
- Color by eye. Light changes the tone of pink gold, and plating can match that tone in photos.
- Weight by hand. Tungsten copies defeat this check.
- Photo inspection of the case back. Plating depth and metal content do not show in a JPEG.
Tests that do work
- XRF scan on a filed or hidden area. A surface scan reads the plating.
- Density test on a removed link. Gold reads near 15 g/cm3, steel near 7.9.
- Serial and reference check with Audemars Piguet.
- Service history from an AP boutique or an AP certified watchmaker.
Legal note
Selling or importing a counterfeit watch is illegal in the United States. US Customs and Border Protection seizes shipments. Trademark law gives the brand the right to sue the seller, and in some cases the buyer.