Horology glossaryDefined term / lume-plot
Lume Plot
The specific pattern, shape, and placement of luminescent material on a dial's hour markers, which varies by reference and production era.
Authentication note
Why this detail matters.
Lume plot shape is a detail that's surprisingly hard to fake convincingly at scale, since it requires matching the exact marker outlines and lume color for a given reference and year. Authenticators compare a watch's lume plot against archival photography of the correct reference and era rather than assuming any plausible-looking lume pattern is acceptable.