When talking about branded replica watches, we normally pay more attentions to the case, bracelet, dial, and material of a fake Rolex watch, the crystal protecting the face also adds its own flair. Whether your Rolex watch has an acrylic (plastic) crystal or a sapphire crystal, it depends on the era. If you have no idea about which one you have, read on to find out the differences between acrylic and sapphire to see what crystal your replica Rolex watch has. 
Vintage Rolex watches consist of acrylic crystals on them and while many may assume that sapphire crystal is naturally much better, and the plastic glass has its benefits too. To begin with, some vintage Rolex watch collectors simply like the look of acrylic over sapphire. Acrylic is less shiny and lends a cool retro vibe to the watch. In terms of practicality, acrylic does get scratched quite easily, but it’s also simple to buff out the scratches in several minutes using polishing pastes. The good news is that acrylic is durable and quite resilient to breaking. Besides, if it does break, it does so in a clean manner rather than shattering. Another advantage of acrylic is that it is rather cheaper to replace than sapphire.
Synthetic sapphire crystal has a much sleeker look and provides superb transparency to view the dial. What’s more, since sapphire ranks so high on the Mohs’ scale of mineral hardness, it is much more scratch resistant—a great bonus for watch wearers. However, because of its hardness, sapphire will also shatter or chip if hit at certain angles. If this happens, not only does the watch need a new costly sapphire crystal replacement, the movement also needs to be looked at to see if any shards landed in there.
Rolex then equipped sapphire crystal again on the Rolex Date replica model and the Rolex Datejust model. While these two watches shared the same angular case shape and integrated bracelet as Rolex’s quartz watches, they were actually automatic watches. When Rolex launched the Oysterquartz collection powered by in-house quartz movements in 1977, sapphire crystal was used again. 
In the end, in the early 1980s, Rolex used sapphire crystals on the Submariner replica watch and actually began equipping all their watches with it. In summary, to see what crystal your Rolex watch has, you can either examine how it looks or find out the date of the watch.