Bronze Watch Case: What to look for in a bronze timepiece?

Bronze is really pretty. We know it. While we will always preach about Bronze’s qualities, it is important to know that not all bronze watches are the same. In order for you to make the most out of your money, here we will give you some tips on what to look for in a bronze watch case.

Things to consider when purchasing a Bronze Watch Case

Always Mind the Alloy

As we’ve covered in the past, Bronze is an alloy made out of the mix of mainly copper and tin. However, there are very different types of Bronze, each made out of a different combination of materials. Here we will break down the most important for you.

bronze watch case

AlCu Aluminium Bronze

This alloy uses Aluminium instead of tin as the main secondary material besides copper. This gives the alloy a particularly bright golden color. Like its siblings, it sports high seawater corrosion, which makes it perfect for a Diver Watch. When exposes to oxygen, Aluminum bronze creates what is called "alumina", which is a small layer of oxide that, like patina, protects your watch. Due to this extra component, the patina on your aliminium bronze watch may be slightly different that the one you are used to.

bronze watch case

Silicon Bronze

As the name would suggest, this mix employs silicon (around 3%). This makes it a lot more ductile, and is amongst the easiest bronze alloy to weld. It is used in several situations where regular bronze excels, and due to its flexibility it is also used in sculptures.

CuSn 6 CuSn 8 Phosphor / Tin Bronze

CuSn 6 and CuSn 8 are terms both used to name phosphor bronze, which is another way to name the main tin and bronze combination.  It is made usually of 1% Tin and around 0.30% phosphorus. This mix is highly sought after due to its low ammount of impurities, and because it hardly gets any reaction from oxygen. This, in turn, makes the material all the more resistant to all possible forms of corrosion.

The difference between CuSn 6 and CuSn 8 comes from the final % of Copper in the mix, with 8 possessing the most ammount.

bronze watch case

The Fonderia Navale Stella is made of CuSn6 Bronze


While all of these make for great bronze watch cases, you can safely state CuSn8 is the best, at least from a chemical perspective.. That’s why CuSn8 timepieces tend to be rather pricier. Here at Pontvs we’ve created watches with AlCu, CuSn6 and CuSn8 Bronze.

If possible, ask the watch brand you are interested in purchasing a watch from what alloy are they using. If they can’t provide a clear answer: RUN. While of course we know that watch prices are subjective, don’t go paying over the top prices for low quality materials.

To Patina or Not

You’ve probably have read that patina is the one and only reason to choose a bronze over stainless steel. These claims are rather right, as it is, without a doubt, a key differentiator from steel or another material.

bronze watch case

Patina is a thin film that slowly develops on bronze and brass surfaces. It has a blue or greenish color, depending on the type of bronze and the elements it has been exposed to. Since everyone’s experience and journey with its watch is different, this actually means that the each watch patina will be different, and thus create an unique look. No two bronze watches will look identical over time.

However, we do understand that not every single person likes patina. So, you’ll have to make a decision of whether or not you’ll opt for this aesthetic or not. And yes, it is a somewhat meaningful decision because the way you treat your watch, and even the way you clean it, will have an impact on the desired outcome.

You could also even accelerate the rate at which your watch patina develops. However, we do not encourage it with your Pontvs or Fonderia Navale watches, as the process, especially if you are not that careful, could end up permanently damaging your watch.

But worry not! Patina is a reversible process; so even if you end up disliking your decision to go for it, you can clean it up using household ingredients in no time! We are currently working on a guide on how to clean it up, so stay tuned for more details.