Colorful bezels are an interesting way to bring life and soul to a watch. Next to pumping up sales, they actually serve an important function. There are two kinds of colorful bezels, and each type has a totally different task.
Let’s start with the GMT watches.
GMT bezels can be explained easily: they track a second (and sometimes third) time zone.
If your colorful watch has a GMT function, the color on hour bezel should be split 50/50. This is done to mark day and night. Sometimes it’s claimed that they mark AM and PM, but that statement is wrong.
Of course, you don’t need to know the difference between day and night on your primary time zone. If your watch tells you it’s 2:15 and the sun is shining, you probably know it’s daytime. No need to check it’s the middle of the night. If you track a second time zone, this can be much harder to do. Having different colors makes it easy to determine the difference between day and night
While your watch works on a 12 hour scale (your hands have the same position at 2:15 and 14:15) a GMT works with a 24 hour scale. While your hour hand makes 2 full rotations in a day, your GMT hand makes just 1 rotation per 24 hours.
This way, you don’t miss a deadline by 12 hours or accidentally call your family in the middle of night if you are abroad. Today, this problem is solved with internet and digital phones, but in fifties, sixties and seventies, a frequent traveler had to do some quick math before calling the wife and kids to check his local home time. A GMT watch could solve that issue.
Let’s dive (pun intended) into the world of dive watches
There are different explanations for colorful bezels with dive watches. These can be used to time up to 60 minute dives more easily. The only problem: colors fade away deep under water. Water absorbs different wavelengths of light at different depth. The longer the wavelength of the color, the lower the energy, and the faster the color turns grey for the human eye.
At perfectly clear water, the color red fades away after just 5 meters deep. Orange goes away after 10 meter, and green after 30 meter. Blue is one of the strongest colors, and turns grey below 60-80 meter.
This makes the famous red & blue and red & black combination rather useless under water. Even the famous blue and orange Planet Ocean bezel stands no chance when diving deep.
Some very affordable watchbrands don’t really seem to know what these colors stand for. There are some weird watches available that have GMT bezels, but no GMT function. Or even worse: a dive bezel but close to no water resistance. These mistakes only happen on low tier watches.
So why would some brands use colors that don’t serve a real function? For the same reason that you wear colorful sneaker. Because they look good.