RE: [Demo notebook] Reference notebook: corrections and recurring beginner questions · RWI-00544

Case 9 — Crystal types: sapphire, mineral and acrylic trade-offs for daily wear

Summary. Pick sapphire for scratch resistance in low-impact use, acrylic for impact tolerance and easy polishing, and mineral as a low-cost middle option. Prefer inner-surface AR if you're worried about wear. Look at crystal profile when comparing thickness. Choose by how you'll use the watch, not by the material label.