Sapphire Crystal vs Mineral Glass — Why It Matters

Every watch crystal looks the same from a distance. Scratch one with your keys and you'll know the difference immediately.

The three types of watch crystal

Mineral glass

Standard glass, heat-treated for hardness. Rated 5–6 on the Mohs hardness scale. Scratches from keys, coins, concrete. Common in budget watches.

Sapphire crystal

Synthetic sapphire rated 9 on the Mohs hardness scale. Only a diamond (rated 10) is harder. Used in Rolex, Omega, Patek Philippe — and on most of the automatic watches we sell.

The Mohs hardness test

Your keys are rated 5.5. Sand is 7–8. Sapphire at 9 means virtually nothing in your daily environment can scratch it.

Why we favor sapphire

Most of the watches at Wear444 use sapphire crystal instead of mineral glass or hardlex. Some of our budget quartz watches use mineral glass, so look for "sapphire" in the product title or specifications before you buy — if it isn't listed, ask us at support@wear444.com.

Browse watches with sapphire crystal in our Best Sellers collection.