Learn more about the Four Cs and how to optimize searching for diamonds online while staying in your budget. Using our diamond charts, you’re sure to find the perfect diamond. [Reading time: 11 min]
Should I Buy a Diamond Online?
After seeing how complicated choosing a diamond online can be, you may be wondering if it’s easier to go to a brick-and-mortar stone. While it may be easier to find the sparkliest diamond in person, you’ll be paying a premium, sometimes thousands of dollars extra! Buying a diamond online from a reputable dealer allows you to put that money toward a larger, better-cut stone or a more intricate engagement ring design.
In this article, we’ll help you narrow your choices from the hundreds of thousands of diamonds available to the one that best matches your ring design and budget.
As with any major purchase online, check the return and exchange policy. If you decide that your diamond isn’t quite what you expected, you want to be sure you can get your money back!
Cut Quality Parameters for Online Diamonds
When it comes to diamond cuts, “Very Good” isn’t good enough. Cut quality is what gives a diamond its sparkle, so if you compromise on cut, you’ll end up with a lackluster diamond.
Take a look at this side-by-side comparison.
The excellent cut 1.20-ct diamond performs MUCH better than the 1.20-ct with only a good cut — and for $2,500 less! The more expensive diamond has a higher color grade, but these slight differences in color are nearly imperceptible. What you’ll notice most about a diamond is its sparkle, so spring for the best diamond cut.
If you’re looking at different diamond shapes, take a look at our guide for your favorite shape:
It’s important to consider which laboratory graded the cut. Some laboratories have looser standards or are less consistent than others.
To be sure of the quality, limit your results to the Gemological Institute of America (GIA) and the American Gem Society (AGS). You can often find this information using the advanced search option on the online retailer’s website.
Polish and Symmetry
You may be tempted to limit their result to “Triple Ex” stones — those rated “Excellent” for cut, polish, and symmetry. However, polish and symmetry have little effect on performance. A rating of “Good” or better is enough.
A diamond’s table is the large, flat facet on top of the stone. Table size or table % tells you how wide the table is compared to the width of the diamond. When the table is too large or too small, light exits out the back of the diamond instead of back toward you.
Ideally, table size is 54-57%. However, diamonds can still show excellent performance with table sizes from 53 to 59%.
The depth % in a diamond tells you the ratio of depth to width. If a diamond is cut too deep or too shallow, light escapes out the back, reducing the amount of light reflected back to you. That means it performs poorly.
To avoid shallow and deep cuts, limit your search to diamonds with an ideal depth percentage of 61 to 62%. If you need a few more options, you can look for depths of 59 to 63%.
Hearts and Arrows
Certain diamonds with ideal cuts exhibit a distinctive pattern of hearts and arrows. However, it’s worth noting that hearts and arrows don’t define a well-cut diamond. While the hearts-and-arrows pattern is attractive when looking at the diamond straight on, what’s most important is assessing the diamond’s performance.
Unless you have a strong preference, don’t limit your search to hearts-and-arrows diamonds.
Diamond Cut Quality Chart
When you’re searching for diamonds online, use this chart to help you find the top quality diamonds. Remember, keeping to these parameters does not guarantee top quality, but it does give you a good indication of whether or not the diamond will perform well.
No diamond is absolutely perfect, even flawless ones. Every stone that nature makes has imperfections. In some, the imperfections are large and obvious. In others, they’re microscopic.
The highest diamond clarity grades range from F (flawless) to IF (internally flawless), VVS1, and VVS2 (very very small inclusions). They designate imperfections visible only under high magnification. Diamonds with these high clarity ratings are priced at a premium, but unless you use a jeweler’s loupe, you won’t notice the difference between these clarity grades and lower ones.
VS1 and VS2 stones (with very small inclusions) are also eye clean in almost every case! However, clarity is graded relative to the size of the diamond, so a flaw might be noticeable in particularly large gems.
The imperfections in SI1 and SI2 stones (small inclusions) are rarely noticeable to the untrained eye. While the imperfections are visible, you would need to inspect the diamond very closely to find them. In this clarity range, dark inclusions near the center of the stone, like this 1.07-ct SI2 diamond, could impact its appearance. Take care to avoid these.
Although finding an attractive I1 (included) diamond is difficult, it’s not impossible. These diamonds will have several imperfections, and finding one whose imperfections don’t detract from its beauty may take some time. If your budget is tight, it may be worth it.
Clarity Grade Recommendations and Chart
This diamond clarity chart gives a quick summary of our recommendations for diamond clarity grades.
For round brilliant diamonds, aim for VS2 and SI1 grades. If your budget is tight, you could spend some time looking at SI2 or even I1 stones. Remember to avoid dark spots near the center of the diamond.
For large diamonds, consider a VS1 stone.
Color Grades and Engagement Ring Styles
Diamond color grades rate how colorless the stone is. Each step is tiny and barely perceptible. Still, these steps can have a big impact on price. The GIA color grades for white or colorless diamonds range from D (colorless) to Z (light yellow tint). The closer to Z, the stronger the yellow tint.
Without directly comparing diamonds side-by-side, few could judge if the diamond they’re seeing is a D or an H. Even side-by-side it might be difficult. Try it for yourself in our diamond color quiz!
What’s important for an engagement ring is that the diamond doesn’t appear off-color. The colors of the ring metal and any gems next to your diamond will also influence whether it appears off-color.
Color grades are less important with a standalone diamond. However, the color of the ring metal still makes a difference in whether the diamond appears off-color.
For white gold and platinum settings, I and J color diamonds will give you the most for your budget. Search the James Allen database based on our recommendations for white gold solitaire rings.
Yellow gold rings mask color, so a K or L color solitaire in yellow gold will still look great! Search the James Allen database based on our recommendations for yellow gold solitaire rings.
Rose gold, popular for vintage styles, is even better at masking color, and even an L or M color diamond with a slight brown tint will look beautiful. Search the James Allen database based on our recommendations for rose gold solitaire rings.
A halo of diamonds makes the center stone appear larger, but when the halo is a much higher color grade than the center stone, it’s simply less attractive. Take a look at the average color used for the setting, usually F to H. It’s best to stick to a similar color grade. Still, you may be able to go 1 to 2 grades lower without any noticeable color.
For diamond halo settings, stick to H, I, and J grades. Also, avoid diamonds with brown hues, which will be more noticeable against the small stones. Search the James Allen database based on our recommendations for halo rings.
When a center diamond is flanked by smaller diamonds on either side, it appears larger. However, it’s again important to note the color of the side stones. Side stones are often G to I in color, and it’s best to have a similar color center stone.
For three-stone rings, H, I, and J color center stones work best. Again, avoid diamonds with brown hues. Alternatively, ask customer service for side stones of a lower color grade to allow your centerpiece to shine! Search the James Allen database based on our recommendations for three-stone rings.
Colored Gemstone Halos and Side Stones
A dash of color next to your diamond won’t have the same effect as bright white diamonds. You can use the diamond color grade recommendations for solitaire rings in this case.
Diamond Color Chart
When it comes to color, you’ll get the most from your budget by choosing the lowest color grade that will look white. Here’s a handy little chart to help.
What to Look for in Your Search Results
Once you’ve narrowed the field with these recommendations and your budget and carat criteria, take your time judging how these diamonds perform. Even though they all look sparkly, some sparkle better than others, and some even sparkle differently.
Take a look at these two diamonds. Both have ideal cuts and great sparkle, but one has a LOT of fire, or flashes of color, while the other has a more even balance of fire and brilliance, or white flashes. Choosing one over the other is largely a matter of preference.
Keep in mind that the clarity imperfections you see at 20x magnification are often invisible without magnification. Try looking at the inclusion while zooming out. If you can still see it, look for another diamond.
In case you haven’t been taking notes, here’s a chart with our recommendations to find the top quality diamond.
What’s the Best Website to use When Searching for Diamonds Online?
Both Blue Nile and James Allen provide close-up 360° images of their diamonds, allowing you to see your diamond in detail before you buy. Both have extensive databases and excellent customer service as well! That’s why we recommend using these vendors, so you don’t have to risk a low quality stone.
However, James Allen has a couple of advantages over Blue Nile. Their selection of ring settings is impressively large. Better yet, you can see color and carat combinations in the ring you’re looking at — in 360° — giving you an idea of what the final product will look like!