How durable is aquamarine?

Aquamarine has good overall sturdiness, with a Mohs hardness around 7.5 to 8, so it is highly resistant to being scratched, but even so, its crystalline framework still needs shielding from hard direct hits.

Since it usually forms in big, cleaner crystals with few internal inclusions, aquamarine tends to show reliable structural stability. It is hard enough to withstand scuffing from everyday grit and many softer things, yet because it is beryl-based, it can still chip if it gets struck with real force against a tough surface, so bezel or tightly secured prong mountings are advised for rings that get a lot of wear.