Rolex Luminous Material (Lume)

Why lume matters

For vintage fans the "correct" lume is a must. Over the years Rolex, and other brands too, used different kinds of luminous material on dials, hands and the lume dots of the bezel. What matters to a collector is that the lume fits the year the watch was made and, if possible, that dial, hands and bezel still have the same lume, ideally even in the same color. The old lume ages badly (it turns yellow and crumbly), so when a watch goes in for service at Rolex, the hands get replaced and often the dial too. Rolex even has an instruction by now that dials and hands with tritium have to be replaced and disposed of during service because of the health risk to watchmakers. That instruction applies to Rolex itself and to every authorized dealer who does services. So there's a very real risk of getting your watch back with a new dial and new hands.

That's not good for the value of a vintage watch, but it is for how well it works. Everybody has to decide for themselves whether to hand the watch in at Rolex or an authorized dealer with a note saying "keep dial, hands and bezel" (and risk that the service gets declined), or go along with the replacement. It depends on how you use the watch: tool watch or collectible. If Rolex declines a service because the dial and hands can't be replaced, your only alternative is a small independent watchmaker who doesn't have to follow Rolex's instructions.

From radium to Super-LumiNova

Until the end of the 1950s the material was radium, which is radioactive and glows on its own. After that it was replaced by tritium, which is less radioactive. In 1998, backed by legal requirements, the non-radioactive Super-LumiNova arrived.

The early lume had the advantage of glowing on its own, but the disadvantage that the glow faded fast after a few years because of radioactive decay. Today you'll find only a few watches, made late in the period, that still glow a little. Most watches don't glow anymore. Luminova and Super-LumiNova always work, but they have to be charged by a light source first. In the dark the glow fades quickly over time.

The print on the dial

The print on the dial tells you easily which lume was used on it:

• 

  Print: SWISS

  Lume: radium

  • Used until about 1960
  • radioactive
• 

  Print: SWISS - T < 25

  Lume: tritium

  • Used from about 1960 to 1998
  • radioactive, radiation below 925 MBq (25 mCi)
• 

  Print: T SWISS T

  Lume: tritium

  • Used from about 1960 to 1998
  • radioactive, radiation below 277 MBq (7.5 mCi)
• 

  Print: SWISS

  Lume: Super-LumiNova

  • Used from 1998 to 2000
  • not radioactive
• 

  Print: SWISS MADE

  Lume: Super-LumiNova

  • Used from 2000
  • not radioactive
• 

  Print: SWISS MADE

  Lume: Chromalight (blue)

  • Phased in from about 2008 (Deepsea)
  • not radioactive

Gold and steel indices

There are two more kinds of print on the dial. They don't point to the lume, they point to the material of the hour markers.

• 

  Print: o SWISS o / o SWISS MADE o

  Gold indices
• 

  Print: - T SWISS T -

  Steel indices

  • Lume: tritium
  • Used until 1998
  • radioactive