Watches have always been an accessory that expresses personal style, and the metals from which a watch is made plays a significant role in that expression. From traditional yellow gold to unconventional materials like carbon fiber, watchmaking has evolved over time to incorporate a wide range of materials to create timepieces that are both functional and aesthetically pleasing while reflecting the wearers personality and status.
The use of yellow gold in watchmaking dates back to the 16th century when clock-watches first became popular, culminating in the creation of the first wristwatches in the 19th century when pioneering watch brands like Patek Philippe and Vacheron Constantin were among the first to incorporate yellow gold into their watch cases and straps, setting the trend for other brands to follow.
Gold is typically mined from the earth in the form of ore or alluvial deposits. Once it is extracted, the precious metal is then refined to remove impurities and create pure gold, which is typically 24 karat. However, the latter is too soft to be used in watchmaking, as it can easily scratch or dent. To create a more durable material, gold is often alloyed with other metals, such as copper and silver, to create a stronger metal. The ratio of gold to other metals can vary depending on the desired color and properties of the final alloy, with 18 karat being the most widely used purity as its 75% pure gold content strikes the perfect balance between resiliance and refinement.
Once the gold alloy has been created, it can be used to manufacture watch cases and straps. Watch cases are typically created using a process known as precision casting, in which molten metal is poured into a mold and allowed to cool and solidify, with the resulting case then being polished and finished to create a smooth and shiny surface, while the latter can be created using a variety of techniques, including cutting and stamping, weaving, or braiding. The gold alloy is typically formed into thin strips, which can then be shaped and crafted into the desired strap design.
Rosé gold, also known as pink gold or red gold, became popular in the 1920s and 1930s, particularly in Art Déco jewelry and watchmaking. This material is characterised by it's higher share of cooper used in its alloy, which gives it a distinctive reddish color. Compared to the aforementioned yellow gold, rosé gold is generally considered to be more durable and scratch-resistant due to the added copper acting as a stronger stabiliser than silver or palladium, both of the latter being highly popular in the forging of yellow gold. Additionally, the copper content in rosé gold makes it more resistant to tarnishing and corrosion. The methods of getting copper have also evolved over time, with the recycling of the metal becoming more and more popular.
Brands like Cartier and Jaeger-LeCoultre were early adopters of rosé gold in watchmaking, being captivated by its warm and rosy hue that gives especially ladies watches a distinctive and elegant look. It remains a popular choice till today, harmonising especially great with lighter skin, as the reddish tone makes the skin look less pale. The methods of mining and processing copper have also evolved over time, with new techniques for extracting the metal from ore and recycling old copper products.
Stainless steel is a durable and corrosion-resistant material that has gained popularity in watchmaking during the early 20th century when cheap wristwatches were required to equip the soldiers in the trenches of the first world war, with the material being long considered as a cheap and shoddy alternative for inferior products. It was not until the 1970s that stainless steel became a popular material for luxury watches, thanks to the success and unbroken popularity of the Oyster line of Rolex and other brands like Omega and Breitling.
The rise of quartz watches in the 1980s and 1990s further solidified the popularity of stainless steel, as it was a more affordable and practical material than the various versions of gold, as well as allowing to be used in various different styles from being polished to a high shine or given a matte finish. Stainless steel is actually an alloy made from a combination of iron, chromium, and other elements. The process of mining and processing the materials needed for stainless steel can be complex, but it generally involves extracting iron ore from the earth and then using a variety of techniques to refine it into pure iron. The chromium and other elements are then added to the iron to create the stainless steel alloy.
One of the key benefits of stainless steel is its resistance to corrosion. This is because the chromium in the alloy reacts with oxygen in the air to create a thin, invisible layer of chromium oxide on the surface of the steel. This layer protects the steel from further corrosion and rusting, which makes it an ideal material for products that are exposed to moisture or other harsh environmental conditions, leading to its wide use in the trenches of the first world war and the sport, field or diving watches of today.
Titanium is a lightweight and durable metal that was first used in watchmaking in the 1970s by brands like Citizen and Seiko. Its high strength-to-weight ratio and resistance to corrosion make it an ideal material for sport and field watches. The metal is usually extracted through open-pit mining, where large machinery is used to remove soil and rock to access the titanium ore. The ore is then transported to a processing plant where it undergoes several stages of refinement, leading to titanium first being separated from other materials through a process called "magnetic separation", which involves passing the ore through powerful magnets. The material is then in the form of a mineral called "ilmenite", containing around titanium dioxide, which must be further refined through reduction and distillation to create pure titanium metal.
Other brands like Tudor and IWC have also incorporated titanium into their watch collections as it can be coloured very easily using anodization. This process involves passing an electric current through the metal, which creates a thin oxide layer on the surface. The thickness of the oxide layer determines the color of the metal, with colors ranging from bronze to deep blue.
Bronze, a metal alloy of copper and tin, has become a trendy material in watchmaking in recent years, with the material boasting a warm brownish colour and high strength as well as corrosion resistance. One of the unique features of bronze is its ability to develop a patina over time, with the aforementioned being a natural layer of oxidation that forms on the surface of the bronze, giving it a unique and rustic appearance.
The process of patination can be accelerated by exposing the bronze to chemicals or other environmental factors, but many watchmakers and jewelry designers prefer to let the patina develop naturally over time. Brands like Panerai, Oris, and Tudor have all recognised the potential of such a versitile material and incorporated bronze into their watch collections, thereby creating timepieces that are truely one of a kind.
Carbon fiber is a lightweight, yet incredibly strong material that has revolutionized many industries and also found its way into the art of horology, giving the watches made from it a sleek and modern appearance. The material consists typically of a type of polymer, such as polyacrylonitrile (PAN). The PAN fibers are then spun into a yarn and treated with heat and chemicals to create a carbon fiber composite material which is incredibly strong, yet also lightweight and flexible.
One of the earliest brands to use carbon fiber in watchmaking was Girard-Perregaux, which introduced a carbon fiber case for its Ferrari 308GTB watch in 1981, with other industry leaders like IWC, Jaeger-LeCoultre or Tag Heuer following hte set example shortly after. However, the most well-known brand associated with carbon fiber watches is probably Hublot, which introduced their "Big Bang" watch in 2004 boasting a carbon fiber case, making it the first watch to incorporate this material on a larger scale.
Ceramic has therewhile emerged as another fairly new all-rounder, with the highly scratch-resistant and durable material being first used by Rado in the 1961s DiaStar 1 featuring a full ceramic case. The aforementioned was made from a high-tech material called "hardmetal," which was composed of tungsten carbide and titanium carbide.
The material was so tough that Rado marketed the watch as "The World's First Scratchproof Watch". Other brands like Omega, IWC or Audemars Piguet have since recognised the materials potential, appreciating the latters scratch resistance, durability, and high-tech appearance.