Which Apple watch face is more resistant to scratches, chips and crac

Sapphire is more immune to scratches, but a fall or hit at an angle can fracture it! It’s also less transparent so in bright light you will have a harder time seeing the screen.

ION-X is less likely to fracture from a fall or hit, but is a bit easier to scratch.

Frankly, unless you work or live with a lot of grit that can scratch your screen I would just go with the ION-X screen. My Apple Watch 2 has yet to get scratched. And its the one I use when I’m at the when I’m bike riding, at the gym or swimming at the pool.