Short answer
The A. Lange & Söhne 1815 Thin is a hand-wound dress watch. Reference 239.050. Honey gold case, 38.0 mm wide, 6.3 mm tall. Movement: L093.1, hand wound, 72-hour power reserve. Lange built 175 pieces in 2020. Replicas use the same numbers in sales copy. Most copies miss the height and the movement.
Genuine specs
- Case: 18k honey gold, 38.0 mm diameter, 6.3 mm height.
- Dial: white grand feu enamel, black printed Arabic numerals, railway minute track.
- Movement: L093.1, manual wind, 2.9 mm thick, 28.0 mm diameter, 167 parts, 21,600 vph, 72-hour power reserve.
- Edition: 175 pieces. The caseback carries the edition number.
- Crystal: sapphire front and back.
Where replicas differ
Height
6.3 mm is the target. An automatic movement adds a rotor and a thicker caseback. Copies of the 1815 Thin measure 8 mm to 10 mm. On a 38 mm case, 2 mm of extra height shows on a caliper and on the wrist.
Movement
The L093.1 has a German silver three-quarter plate, screwed gold chatons, and a balance cock with hand engraving. An engraver cuts each cock with a burin. Copies use stamped or laser-etched plates. Some copies show a rotor. The genuine watch has none.
Dial
Grand feu enamel starts as glass powder. The dial goes into a kiln at about 800 °C. Numerals are printed and fired. The result has depth and a small wave at the rim. Replica dials use lacquer or printed brass. A loupe shows brush marks, a flat gloss, and printed edges that sit above the surface.
Case metal and weight
Honey gold is an 18k alloy. Lange does not publish the mix. Density sits near 15 g/cm3. Steel sits at 7.8 g/cm3. Copies plate steel or brass. Plating wears at the lugs and the caseback rim. A gold case at this size weighs far more than a plated one.
How to tell a replica from the genuine watch
- Measure case height with a caliper. 6.3 mm is genuine. 8 mm or more is a copy.
- Look at the caseback. A rotor means a copy. The L093.1 has no rotor.
- Inspect the balance cock. Hand engraving on the genuine watch. Stamped or laser lines on a copy.
- Compare weight with a steel watch of the same size. Honey gold is near twice the density.
- Check the dial rim under a loupe. Enamel has thickness and a fired edge. Lacquer sits flat.
Market notes
Lange made 175 pieces. Secondhand supply is small. Replica listings show 1815 Thin watches in steel, in gold-colored plating, and with automatic movements. The factory version uses honey gold. Lange made no steel case for reference 239.050.