With black wristwatches celebrating — roughly — a half-century of availability, and they’re certainly enjoying an increase in popularity, it’s easy to see, when looking back, that the biggest challenge has been durability. Early black-coated watches revealed their base metals with the slightest of scratches, whereas later versions yielded to much wear-and-tear before the steel showed through.

Aside from materials that are coloured all the way through, especially ceramics, titanium, plastics and carbon fibre, treatments and coatings are required to make black watch cases. Watchmakers who wish to use the best material of all — stainless steel — have tried everything from baked-on powder coatings to anodising to the latest treatments that work on a molecular level. Here’s Revolution’s guide to the various solutions.

ADLC

ADLC stands for “amorphous diamond-like carbon”, which is applied to the recipient material at 200°C. Its virtues include elasticity, extreme hardness and the provision of a genuinely smooth surface suitable for fine watches. Its durability ensures that it is almost totally scratch-resistant, while also resisting fingerprints. ADLC was developed by Cartier for the ID-ONE prototype watch and reached production in the Cartier Santos 100 Carbon.

AlTin

Used by Urwerk for certain models, including the UR-1001 and UR-202, AlTiN is a specially-coated stainless steel. AlTiN is short for “Aluminium Titanium Nitride”, an industrial surface treatment originally developed to reduce the wear of machine cutting tools. Although these properties were develop for industrial applications, the process exhibiting increased oxidation resistance and hardness, its ruggedness and its semi-matte black colour appealed to Urwerk as a high-tech coating to protect these watches.

Carbon fibre

This now-familiar group of high-tech, composite materials has always boasted a high-strength/low-weight marriage that found instant appeal to car manufacturers, the aviation industry and other applications where strength is paramount and weight anathema. Carbon fibre consists of two components, the woven matrix and the reinforcement, e.g. a resin like epoxy, to bond the materials. It is also inherently black, can be moulded under pressure and has a look (thanks to its inherent weave) that suggests modernity to the general public, in the manner of general evocative terms like “digital”. Carbon fibre watches include models as diverse as Luminox’s rugged Black Ops Carbon 8800 Series and Mazzuoli’s Manometro Carbon Fibre, with the latter’s dial showcasing the weave.

Ceramic

Although no longer new, ceramics for watches still confuse people who automatically picture pottery or bathroom tiles. Modern ceramic materials have revolutionised everything from kitchen knives to medical equipment to loudspeakers, but for watches the main application is as a case material, pioneered by IWC 30 years ago for the Da Vinci. The ceramics in question are non-metallic, with a crystalline oxide, aluminium oxide, nitride or carbide base, with silicon carbide and tungsten carbide the most modern types. Although ceramic materials are brittle, they are hard, can produce a handsome surface finish, withstand high temperatures and resist compression and chemical erosion. Ceramic watches are now a sub-genre in the watch world, with IWC’s efforts joined by all-black models from Panerai, Chanel, Rado and Bulgari, with companies including Rolex using the material for its bezels.

DLC

Diamond-like carbon, or DLC, is the costlier, go-to finish that has surpassed basic PVD (see below) in popularity thanks to its far greater durability. It is a type of amorphous carbon material that offers the hardness properties of diamond, and the watch industry found it a near perfect material for applying colour — especially black — to watch cases. A nano-composite coating, its diamond-like properties also include low friction and high corrosion resistance, in addition to the hardness. It should be stressed that it is applied as a physical vapour deposit, so it is actually a type of PVD. Examples include the Ball Engineer Master II DLC, various black (non-ceramic!) Panerais, the HYT H1 Dracula and the Speake-Marin Spirit Mk II DLC.

Forged Carbon

First employed by Audemars Piguet for the Royal Oak Offshore Alinghi Team of 2007, and now offered by Tempest in a model selling for under $1,000, forged carbon is a carbon fibre variant registered to a French aeronautical company, in which high pressure is applied to carbon fibre placed in a mould. The resultant shape is more dense than standard carbon fibre, and thus stronger, while being much lighter than metals.

PVD

Physical vapour deposition (PVD) is a generic term that covers a range of vacuum deposition methods, the idea being to produce thin but durable films by first creating a vapour of the coating. It is then deposited on the object to be protected or coloured. PVD’s uses encompass everything from thin film solar panels to food packaging, but watch enthusiasts know it as the first of the modern treatments to replace the fragile powder coating or anodising of the past, and it remains the most popular. Among the coatings applied with PVD are various nitrides including titanium, zirconium, chromium and titanium aluminium nitride (see below). Watches offered with PVD coatings — and the durability has improved markedly since the 1990s — include SevenFriday’s Copper Black, Alpina’s Startimer Pilot, the JeanRichard Aquascope Black and the Sinn 857-UTC-Black.

TiC

TiC is type of PVD that employs titanium carbide and is the finish chosen by Tudor for its new series of all-black Black Bay Dark. It was preferred, says Tudor, because “it has been found to be very hard — 10 times harder than steel — but it is less brittle than DLC (Diamond Like Carbon). This is important on TUDOR divers’ watches as pressure can distort the case and cause issues with coatings coming free.” Notable, too, is the super-smooth finish.

Conclusion

As with everything for which there are so many choices, there is no single “best of” – you have little choice, for example, if you want a black watch in a near-proprietary material, for example forged carbon or AlTin, and only a few companies such as Panerai offer black watches in a variety of materials. What it is safe to say, however, is that all of the modern black treatments – while not quite a match for materials that are black all the way through – will survive far more wear-and-tear than their predecessors of a recently as 15 years ago. And if you’re considering any watch made black by an aftermarket concern, the above should help you choose the one that will withstand day-to-day use and abuse.

Just in case you’ve missed part 1 of Ken Kessler’s series on black watches, read part 1 here, when Ken discusses how black watches came to being.

Editor’s note: In the opening image, Dwayne “The Rock” Johnson is sporting a Panerai Luminor 1950 3 Days GMT Automatic Ceramica – 44mm.