Stainless steel is the choice material for most watches because of their notable corrosion resistance – quite vital with sweat and moisture always coming in contact with your watch.
Most watches today use a stainless steel graded 316L. But, Rolex being Rolex, the company uses a unique blend of high-quality 904L stainless steel made by their in-house foundry. Just recently, it has been baptized as the Oystersteel.
Rolex first started using the 904L steel for the Rolex Sea-Dweller, their line of ultra-resistant professional diving watches. The rest of their steel watches still used the industry standard 316L.
But over time, they learned that while 316L is corrosion resistant, salt water can still inch its way into the caseback threads and watchbands of its steel watches, eventually causing rusting and pitting.
In 2003, they shifted all of their steel watches to 904L – a decision not taken lightly. Since 904L is tougher and is a very particular type of steel, this meant changing all the equipment used for their steel watches.
2. “Oystersteel” started appearing in Baselworld 2018.
The term Oystersteel only started appearing this year, beginning with the new line of GMT Master II watches. A closer look at Rolex’s website reveals that they have quietly replaced the “904L stainless steel” in their literature.
Since no distinction was made between the two metals, it’s likely that it is now Rolex’s name for the 904L stainless steel that they use on their watches. A trademark name for their in-house metals or their combinations, just like Everose (rose gold) and Rolesor (half-steel, half gold).
3. Oystersteel is a steel superalloy specific to Rolex, which belongs to the 904L steel family.
So what exactly makes 904L different from traditional steel?
904L is a low-carbon, high alloy stainless steel, with additives of copper, chronium, nickel and molybdenum. Most commonly used in the aerospace and chemical industries, 904L has excellent anti-corrosion properties, that are comparable to those of precious metals.
It also gives off an exceptional sheen when polished – helping maintain its beauty even when exposed to elements.
SEE MORE OF THE WATCHES IN OUR VIDEO: