4 Carat Diamonds

Celebrate your love in bold, brilliant fashion with a stunning 4 carat diamond from Blue Nile. This statement-making size is dazzling in any piece of jewellery, pairing beautifully with all setting styles. Enjoy a classic look with a round brilliant diamond, or bring a unique flair to your piece with one of our fancy-shape diamonds. As you shop our 4 carat diamond selection, choose a higher cut grade for matchless brilliance.


20 of 505 4 Carat Diamonds

FAQs about 4 Carat diamonds

Shape, colour, cut, clarity, and carat all affect a diamond's price. A 4 carat loose diamond can range in price from about $28,000 to $160,000.

The shape of a diamond helps determine the 4 carat diamond size. A 4 carat round diamond measures around 10.2mm, but the same carat weight in a marquise cut can measure 17mm x 8.5mm. This diamond carat size chart compares all shapes and carat weight options.

Of all of the 4 Cs, the cut should be prioritized. The cut of the diamond determines the light reflection. Diamonds with an ideal grade or higher will provide maximum brilliance.

Carat plays the biggest role in the final price of a loose diamond. If you choose a stone just under the carat weight you want (e.g., a 3.9 carat weight instead of 4.0), you'll save on the price of the diamond. This is called "buying shy."

Top 4 Carat Diamond Reviews

A closeup of a hand with multiple different shapes and sizes of diamonds.

One in a million. The very best!

With your amazing help, I not only got a stunning ring at a very reasonable price, but she said YES!
Jeremy W. - Verified Buyer
Average Customer Rating $5 out of 5 stars
Asscher Cut Diamond Engagement Ring
Platinum (1 ct. tw.)

MOP 44,400.00

now: MOP 31,080.00


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