Explore Diamonds
STYLE GUIDE
What’s Your Fancy?
Fancy-shaped diamonds give you a chance to express your unique personality.
DESIGN YOUR OWN ENGAGEMENT RING
CURRENT FAVORITES
Hello, Pretty Yellow Diamonds
Only one in 10,000 diamonds has the distinct natural hue of a colored diamond. Options span the spectrum, from yellow to blue.
Crafted for You
Our highly skilled artisans strive to exceed industry standards with sparkling certified diamonds, thoughtfully-sourced materials and outstanding engagement ring design at an amazing value.
Top Questions and Answers About Diamonds
Welcome to the Blue Nile Diamonds FAQ, featuring everything you need to know to maximize sparkle—and your budget. As the largest online retailer of certified diamonds and fine jewelry, we can say with confidence that you’ve come to the right place to buy a diamond or completed engagement ring.
What are the 4Cs of diamonds?
The value of a diamond is determined by the 4Cs—cut, color, clarity and carat. The most highly valued diamonds are colorless with a precisely fashioned cut and few blemishes. The 4Cs shouldn't be the only considerations for buying a piece of diamond jewelry, though—what's most important is how it makes you feel.
What are lab-grown diamonds?
Lab-grown diamonds are made from the same material as natural diamonds—pure carbon. Lab-grown diamonds are optically identical to natural diamonds—the only difference is in how they’re formed. Instead of growing over millions of years, these diamonds are created using a cutting-edge technology that replicates the natural growing process in a matter of weeks.
What are conflict-free diamonds?
Conflict-free diamonds are diamonds that were not used to support civil wars and don’t bear a connection to rebels or terrorist groups. All of our diamonds are certified conflict-free and are never sourced from areas with reported human rights abuses. Thanks to the Kimberley process, an international process for certification that follows diamonds from the mine to the market, it's easy for us—and the global diamond industry as a whole—to provide diamond lovers everywhere with documentation that their gemstones were responsibly sourced.
What are the different kinds of diamond shapes?
Diamond shape refers to the silhouette of the gemstone. There are 11 popular diamond shapes — Princess, Cushion, Heart, Pear, Marquise, Radiant, Asscher, Emerald, Round, Trillion and Oval. Each shape has its own sense of rapture and brilliance, and the most important factor in choosing a shape is how it makes you feel.
What are loose diamonds?
Loose diamonds are diamonds that have been cut and polished, but they have not been placed in a setting. They are ready to be placed into jewelry.
Where is the best place to buy diamonds?
When buying loose diamonds, you want to be sure that you understand the specs and certifications of the stone. The best place to buy loose diamonds is a place where you can read the diamond’s IGI or GIA certifications, look at detailed photos of the stone and reach out with any questions you may have. We are proud to offer not only a leading selection of loose diamonds for sale but also a positive experience for a worry-free purchase.
Which diamonds are the most popular?
There are many diamond shapes that are popular today, with round brilliant often getting the most demand. But other shapes, such as princess and oval, are growing in popularity.
What is certified diamond?
Diamonds that have been reviewed by the GIA or IGI for their ratings of the 4Cs are certified diamonds. These diamonds come with a certificate that attests to their unique characteristics including cut, color, carat and clarity. Certified diamonds also have their own unique report numbers.
How to buy loose diamonds?
Today, buying certified diamonds is easier than ever before. We invite you to browse our large selection of certified loose diamonds for sale in many shapes and sizes. To purchase any of our loose diamonds, simply select the diamond you’d like and complete the checkout process.
Are diamonds durable?
Diamonds are the most durable of all the gemstones. A 10 on the Mohs scale of hardness, diamonds are perfect for everyday wear and can last forever. This makes them the perfect stone for engagement rings.
What jewelry looks best with diamonds?
Sparkling diamonds are beautiful in every jewelry setting. They are popular for wedding styles such as wedding rings but can also be found in everything from cross necklaces to tennis bracelets. The impressive durability of diamonds makes them perfect for daily wear pieces.
How are diamonds added to jewelry?
Loose diamonds are placed into jewelry through settings that hold the stone in place. For rings, these are typically settings with prongs that keep the diamond secure. Common diamond settings in other types of jewelry include bezel settings that wrap around the stone.
How can you tell that a diamond is real?
Diamonds are incredibly durable stones that can last generations, but other stones like moissanite and cubic zirconia are diamond simulants. Fake diamonds often do not have the brilliance of a real diamond. They may look like they're made of glass, or they chip easily. There are several home diamond tests that can determine whether your diamond is authentic.
The fog test is a common way to check if a diamond is real. Blow air onto your diamond, a real diamond will quickly disperse any fog that gathers from the warmth of your breath.
Of course, the best way to tell if a diamond is real is to buy it from a reputable jeweler. At Blue Nile, we only sell real diamonds and offer transparent reporting on our stones.
Is it safe to buy diamonds online?
Yes, it is safe to buy diamonds online when shopping from trustworthy jewelers. We allow you to inspect your diamond up-close with high-quality photos, IGI or GIA certifications and even 360° viewing for many stones. If you are looking to buy a diamond, you have come to the right place!