Using photoluminescent material to show the time in low-light conditions is a practice that has been employed since the development of the earliest wristwatches.
Originally, radium was used on hands and indexes, which had the benefit of a bright and long-lasting glow, counterbalanced by the disadvantage of being highly radioactive and a major health issue for those who applied it.
In the 1960s, radium was replaced by the much safer, yet still radioactive, tritium, which was phased out in the 1990s when alternatives like strontium aluminate (in the form of Super-LumiNova) came to market.
The idea behind practically all forms of ‘lume’, though, is that they absorb light during the day, store it and then emit it in the dark. The most common colours are blue, green and white, but this is by no means all that is available. Usually coating hands and indexes, the more adventurous manufacturers – like the ones listed below – have found ways to add light shows to dials, bezels, cases and even straps.
Ball Watch Co. Engineer III Marvelight Chronometer
According to Ball watch, the self-powered micro tubes that have become its trademark are 100 times brighter than standard luminous coatings, and, although the glow will gradually fade over time, a replacement dial will easily solve the problem. The illumination is achieved through H3 tritium gas, safety-sealed in mineral glass tubes that are coated with a luminescent material. And nowhere is the light brighter than in the recent Engineer III Marvelight. With rainbows now a symbol associated with 2020 and the global fight against Covid-19, Ball has issued the limited-edition 40mm watch with multi-coloured gas tubes. For every piece sold, 300 Swiss Francs will be donated to The Salvation Army.
Price: £1,800 | Ball Watch Co.
Bell & Ross BR03-92 Diver Full Lum
With this new limited edition piece, Bell & Ross playfully reverses the traditional principles of day and night legibility. The 42mm Diver Full Lum sees its metal dial fully coated with green Superluminova C5, while the indices and bezel numerals are filled with Superluminova C3. Diver capabilities come in the form of a 38-hour power reserve, water resistance to 300 metres, as well as a woven black rubber and resilient black synthetic fabric straps. But it’s the delicate balance of visual weight between dial elements and that all-over lume treatment, which extends to the date window, which sets this watch apart.
Price: £3,800 | Bell and Ross
Rolex GMT-Master II
This 40mm Oystersteel and ‘Everose’ gold Rolex with black dial and a brown and black Cerachrom bezel is designed primarily to show the time in two different time zones simultaneously during intercontinental flights. And while it features Rolex’s caliber 3285 movement, which uses the Chronergy escapement and is regulated to an +2/-2 seconds per day with a power reserve of 70 hours, what shines out here is the use of Chromalight. In 2008, Rolex debuted its Chromalight lume on its Deepsea Sea-Dweller. Rather than green, Rolex’s proprietary photoluminescent compound glows blue in the dark. Rolex states that Chromalight can last up to eight hours, more than double the time of other luminescent materials.
Price: From £7,750 | Watches of Switzerland
Zenith Defy 21 Carl Cox Edition
What better way to put a stamp on a watch collaboration with a superstar house DJ than by adding a shock of acid green lume? By day, the limited-edition Defy 21 Carl Cox is a technical-looking, 44mm carbon-cased, skeletonised chronograph. But by night, it takes on an aesthetic straight out of late-1980s rave culture. A new interpretation of Zenith’s 1/100th of a second chronograph, the watch has Super-LumiNova-coated hands and indices, as well as luminescent highlights on the running seconds sub-dial that takes the form of a spinning vinyl record. And, succumbing to the ideal that more is more, the carbon-fibre bezel and strap stitching also glow in the dark like a neon smiley face.
Price: £7,800 | Watches of Switzerland | Goldsmiths
Roger Dubuis Excalibur Twofold
Only eight pieces of the deliciously summery Excalibur Twofold have been made, each one a bright shining light of horology. As with the Panerai, the 45mm, snow-white case of the watch is in a mineral fibre composite – although, uniquely, Roger Dubuis has plumped for a material consisting of 99.95 per cent silica.
The watch features the brand’s signature skeletonized, double flying tourbillon movement, turning it into a showcase for the futuristic Super-LumiNova X1, which is applied to the angles of the upper plate, enabling it to light up with a glow that lasts 60 per cent longer than standard lume. The strap is made from a luminescent rubber material with a camouflage pattern.
Price: £212,241 | Roger Dubuis
Panerai Luminor Marina Fibratech 44mm
Panerai has always taken photoluminescence very seriously, even naming its two signature models – Radiomir and Luminor – after the materials used to achieve it in the 1930s and 1950s. However, with the Luminor Marina Fibratech 44mm, the brand takes a playful approach to watchmaking’s night light.
With a case made from layers of mineral fibre, bonded together through heat and pressure, the watch uses Super-Luminova X1 that has a greatly improved performance compared to the standard grade. Panerai has added a glowing coating to the crown protector and crown, as well as the hands and dial legend and the flange surrounding the dial.
The indexes and small-seconds are illuminated thanks to the lume-coated disc below the top dial. And in a final flash of inspiration, the Sportech strap (one of two bands supplied) features luminescent stitching.
Price: £17,100 | Panerai
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