A watch’s case is the most important component that can make or break its durability. Tool watch cases have almost always been made of steel, titanium, and occasionally precious metals (in some less bona fide examples), but now there’s a new kid in town, bronze. With its bold appearance, unique patinating properties, and real-world industrial use, it’s quickly becoming one of the biggest trends within the watch industry. Whether it’s CuSn8, aluminum bronze, or the arguably inferior brass, there’s no doubt these alloys are making their mark.
Massive bronze propeller — Photo courtesy of Business Week
Bronze is an alloy comprised of primarily copper. The secondary metal is usually either tin, which yields CuSn8, or aluminum, which yields an aluminum bronze (of which there are many variations). CuSn8 is commonly regarded as the industry standard, primarily because it’s a marine grade alloy. This means it can be used below the surface in salt water for a lifetime, with virtually no signs of corrosion — thus, the reason for its long history of nautical applications. Aluminum bronze is similar to CuSn8, save for a few differences. As a result of the use of aluminum instead of tin, the price of aluminum bronze is considerably lower. Despite the lower price, quality still remains high, and aluminum bronze is also admired for it’s high strength, and resistance to corrosion.
IWC Aquatimer Expedition Charles Darwin
With tool watch brands like Panerai, Ennebi, and most recently IWC introducing bronze cased watches, other less-notable brands have found a way around the expensive nature of bronze. Allowing them to capitalize on some of the craze, brass has been popping up here and there. Some might see brass to be the same as bronze in many ways, but in truth, they’re far from similar. Brass is less durable than bronze, due to its malleability and tendency to stress cracking when exposed to substances such as ammonia. When it comes down to it, bronze is worth the extra $100, since it gets you a much more robust and long-lasting timepiece.
Watch aficionados have enthusiastically welcomed bronze-cased watches into their collections, namely because of the patinating properties. Bronze’s corrosion resistance can be owed to its ability to superficially oxidize, creating a layer of brownish copper oxide that protects it from the elements; it essentially has a living skin. This just so happens to give the material an aged, battle-hardened look. CuSn8 has been known to take on a deep brown patina, whereas aluminum bronze often becomes a lighter and more reddish shade of brown. Collectors love the unique patina that grows with him or her over time — a clear correlation to the popularity of distressed and vintage styled watches.
If you’re interested in adding a bronze watch to your collection, there’s certainly no shortage of options available on the market, and at all price points. From Ancon to Archimede, and from Steinhart to Panerai, there’s a watch to satisfy any consumer, which is one of the reasons we here at Wound For Life are thrilled with the recent success of bronze cases. It’s a rugged and durable material, with true industrial roots — a positive aspect of any tool watch. Next time you’re browsing through your local watch shop, you’ll know that while bronze cases may seem like the new industry fad, it’s not merely a fashion statement, but a properly tough material.
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