Feature: Top Four Ceramic Watches
Ten years ago, most people would have associated the word 'ceramic' with potted plants and tea parties. After all, the Greek word that ceramic is derived from—kerameikos—means 'for pottery'. But that's all changed now, and ceramics are once again at the cutting edge of material science, harder, stronger and more impressive than ever before. We take a look at four ceramic watches to see just how good the technology really is.
A ceramic material is quite simply an inorganic, non-metallic solid created with heat. The earliest known use of ceramics comes from around 27,000 years ago in the form of fired clay figurines, and it wasn't until the 1940s that companies began development of what are now known as 'technical ceramics'. Most ceramic watches are made of a technical ceramic called zirconium dioxide (ZrO2).
Hublot Big Bang Blue Ceramic
Our first ceramic watch, the Hublot Big Bang Blue Ceramic, has an obvious extra ingredient: blue pigmentation. The pigmentation—along with the binder that helps the ceramic powder maintain its shape before firing—makes up around 3% of the finished material, and maintains its rich, vibrant colour almost indefinitely, unaffected by UV radiation from the sun. The denim blue may not appeal to everyone, but it’s a prime example of how the aesthetic strengths of ceramic materials match the physical.
One of the many great properties of ceramics is the weight—or rather, the lack of it. At 3g/cc it is lighter than both steel (8g/cc) and even titanium (4.5g/cc), and combined with a rubber strap it is extremely comfortable to wear.
Watch Spec
Case: Ceramic Dimensions: 44mm dia, 14.5mm thick Crystal: Anti-reflective coated synthetic sapphire Water Resistance: 100m Movement: Calibre HUB4100, based on ETA 7750, automatic Frequency: 28,800 vph Power reserve: 42 hours Strap: Rubber Functions: Time, date, chronograph
Did You Know? The family of ceramics also includes glass, diamond and even sapphire, the material most watch crystals are made of. They all exhibit the same properties as traditional ceramics: hardness, brittleness and heat-resistance, however the molecular structure found within them differs in its inability to absorb visible light, allowing it to pass straight through.
IWC Big Pilot's Watch Top Gun IW5019
Within the watch industry—and even within pottery—it is common to see ceramic materials polished into a high gloss finish, but that isn’t so for this IWC Big Pilot's Watch. The zirconium dioxide case has a hardness (i.e. scratch resistance) of 8.2 Mohs, which is four times as hard as the 6 Mohs of steel. This level of hardness requires a material even harder to cut and finish it, and that material is another ceramic: diamond.
The result is a textured, bead-blasted surface that scatters light and leaves an industrially matte finish, perfect for a military inspired piece. Complex components like the crown, the threaded caseback and the clasp remain in titanium (something worth noting is that ceramic, like titanium, is inert and hypoallergenic), which breaks up the matte black finish carried over the rest of the watch.
The lightness of the ceramic (and titanium) is very welcome, as the 48mm diameter, 15mm thick case would otherwise be noticeably weighty, especially with the calibre 51111 beating inside. The Pellaton winding system and seven day power reserve—as good as they are—all add extra weight.
Watch Spec
Case: Ceramic Dimensions: 48mm dia, 15mm thick Crystal: Anti-reflective coated synthetic sapphire Water Resistance: 60m Movement: Calibre 51111, automatic Frequency: 21,600 vph Power reserve: 7 days Strap: Canvas Functions: Time, date, power reserve
Did You Know? The first watch with a ceramic case was the Da Vinci, made in 1986 by IWC. Shortly after in the same year came Rado's Integral, a ceramic watch that featured the world's first ceramic bracelet. In 2004, Rado took ceramics to the next level by creating the V10K, a watch made from synthetic nanocrystalline diamond.
Panerai Luminor 1950 PAM00335
Making intricate parts from zirconium dioxide is no mean feat, requiring diamond-tipped machining tools and a whole lot of time. This is why most watchmakers leave the fiddly components well alone, using traditional metals in place of tricky-to-work ceramics—but not Panerai.
With the PAM00335, Panerai took their ceramic production up a notch, producing the crown guard mechanism from zirconium oxide alongside the case and bezel. But why can't the ceramic material just be formed in moulds, to save on the costly and time-consuming process of machining? After all, the raw materials of most ceramics are very affordable: it's the production that adds the cost.
The problem lies in the method used to turn zirconia powder into a ceramic. Mixed with 20% binder, it's warmed into a liquid and injected into a mould. This 'green' stage produces a soft solid, which can be machined into the rough component dimensions. The ceramic is then sintered, reaching temperatures of 1,500°C and cooling down again several times. During this process, most of the binder is burned off, and shrinkage occurs. This shrinkage leaves a rough shape that necessitates further machining.
Watch Spec
Case: Ceramic Dimensions: 44mm dia Crystal: Anti-reflective coated synthetic sapphire Water Resistance: 100m Movement: Calibre P.2003, automatic Frequency: 28,800 vph Power reserve: 10 days Strap: Leather Functions: Time, date, second time zone, 24hr, power reserve
Did You Know? Without any pigmentation, ceramics formed with zirconium oxide are pure white. Another form of zirconium dioxide - one that is completely transparent—is cubic zirconia, which is most famously used as a diamond substitute. The name comes from its cubic crystalline molecular structure, and it has been in production since 1976.
Omega Speedmaster Dark Side of the Moon
So is anyone brave enough to go even further than Panerai? Anyone? Yes, you sir, you at the back: Omega. There are no holds barred when it comes to the Speedmaster Dark Side of the Moon. The case is zirconium oxide—ƒ—yes, I think we could guess that much—but so is the crown, and the pushers, too. Even the buckle is made of the stuff.
But Omega didn't stop there, because if we look just above the hand stack in the middle of the dial, zoom and enhance, we see a small, almost invisible logo: ZrO2. Yes, ladies and gentlemen, boys and girls, even the dial is made with ceramics.
The Dark Side is the best example we have today of what's possible with ceramics in watchmaking. The challenge in making it is emphasised by the limited nature of its production, which for once is not by design, but by manufacture. This watch takes so long to make (twenty times that of the steel version) that Omega can't make them fast enough to keep up with demand. And those who do manage to get one? Keep hold of it. It's a winner.
Watch Spec
Case: Ceramic Dimensions: 44.25mm dia, 16mm thick Crystal: Anti-reflective coated synthetic sapphire Water Resistance: 50m Movement: Calibre 9300, automatic Frequency: 28,800 vph Power reserve: 60 hours Strap: Canvas Functions: Time, date, chronograph
Did You Know? Ceramic materials are very high in compression strength, withstanding up to 600,000 psi (15,000 times that of a car tyre), but have low ductile strength, which means they shatter easily on impact. To overcome this, ceramic matrix composite materials have been developed, which use ceramic fibres to reinforce fracture toughness.
