Apple is rumoured to hold its next event on 10 September and the next iPhones are expected, as well as the Apple Watch Series 5.

There haven't been as many leaks surrounding the Watch Series 5 as the iPhone XS, XS Max and XR successors, but some WatchOS 6 assets have indicated we could see the return of the ceramic casing, as well as a new titanium casing for the upcoming smartwatch.

The assets, found by iHelpBR, show the animation that appears on any Apple Watch when you first set it up. The animation replicates some of the information shown on the back of the Watch casing and the leaked assets suggest a ceramic and titanium model of the 40mm and 44mm are coming.

Apple previously offered a ceramic casing for the Apple Watch Series 3, but it didn't offer one for the Series 4, while titanium isn't a material it has used at all - except for the Apple Card.

It could be the images from WatchOS 6 indicate a ceramic and titanium option of the Series 4 rather than the Series 5, but we suspect it is more likely the new device. New casing materials also suggest that a design change is unlikely this year, with new materials possibly being the focus instead. This would makes sense given the changes last year.

You can read all about what else is expected for the Apple Watch Series 5 in our rumour round up feature, as well as what we'd like to see appear. We also have a feature on WatchOS 6 if you want to read all about what features are coming with the next software build.