Diamonds are forever—but they’re not for everyone. Still, if you’d prefer to go the non-traditional route, you’ll want a hard-wearing stone that stands up to a lifetime of wear. Using the Mohs scale, a ranking of mineral hardness from one to ten, we picked four sturdy, scratch-resistant—and stunning—alternatives that can stand the test of time, plus three stones you might want to think twice about.

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‘Imperfect’ Alternative Diamonds

Mohs rating: 10 

Reminder: Diamonds come in many different forms beyond traditional white sparklers. Trend-forward? How about a moody salt-and pepper diamond, or maybe a sepia-toned rough-cut gem. Très distingué.

Get the look: Alexis Russell ($4,395)

Moissanite

Mohs rating: 9.5 

OK, so this increasingly popular option looks an awful lot like diamonds—but we felt it was worth mentioning them since they’re so much cheaper. While they’re produced in a laboratory, these stones are actually a rare, naturally occurring compound called carborundum—and it’s nearly impossible to tell them from the real thing without a trained eye.

Get the look: Bihls ($350)

Sapphires

Mohs rating: 9

Sapphires are easily the most classic diamond alternative. (Just ask Kate Middleton.) But PSA: They don’t have to be cobalt! Petal pink, coral and even white make chic and contemporary choices.

Get the look: Eidelprecious ($4,200)

Rubies

Mohs rating: 9 

Haven’t you heard? Rosy engagement stones are having a moment. If you fancy yourself a true romantic, consider this durable crimson gemstone, perhaps in a haute Victorian-inspired floral design.

Get the look: Ken & Dana Design (from $2,350)

Emeralds

Mohs rating: 7.5 

We know, we swoon for these regal green stones, too. But since they’re susceptible to scratches and discoloration, you’d be better off leaving them to your earrings or a special occasion cocktail ring.

Get the look: Capuccine (from $5,600)

Morganite

Mohs rating: 7.5

This increasingly trendy stone is a strain of beryl: a mineral found in aquamarine. While we’re thoroughly obsessed with the peachy-pink color, it’s sadly a risky engagement ring choice, due to its moderate softness and susceptibility to damage.

Get the look: Lamore Design ($898)

Amethysts

Mohs rating: 7 

These precious stones are dramatic and gorgeous. But they’re also susceptible to chipping, breaking and damage from heat or chemicals. Again, a better choice for jewels that don’t take such a beating.

Get the look: SevenCaratShop (from $1,100)

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