A tropical dial is the dial of a vintage watch whose colour has changed as it aged. The classic change is from black to brown. Sunlight, humidity and other conditions bring it about. What began as a fault in the paint is now a feature that many collectors seek out.
What causes a tropical dial?
The effect started as a fault. The paint that dial makers used had a chemical defect in its manufacture. Over time, UV light browns the dial and yellows the luminous material on it. Water damage often adds to the effect. The classic case is a black dial that has turned brown. How far and how evenly a dial changes depends on where the watch has spent its life, and on how much sun and damp it has met.
What makes a good tropical dial?
Collectors like most the dials that went from black to light brown slowly and evenly. A naturally faded dial with a completely even colour is hard to find. Blotchy dials that look mouldy or water-damaged are less sought after. Buyers also prefer dials aged naturally by sunlight to dials aged by artificial means. So a change of colour alone is not enough. What counts is how the dial changed.
Where it comes from
The nickname points to the tropics, where strong sun and high humidity come together. Collectors use the word tropical for a dial that faded after years in strong sun. The term is said to have come into use among collectors in the 1990s. Some people think dealers came up with the name to make a defect sound appealing.
Which watches have tropical dials?
Tropical dials turn up on many Swiss brands, including Tag Heuer, Tissot, Longines, Certina, Eterna, Helvetia and Cyma. The look is no longer limited to old watches. Some brands now make new watches with dials that are tropical by design. Nivada Grenchen did this so that the look would cost less. On these watches the colour is chosen at the start, not earned through age.
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