princess-cut engagement ring - what to know before buying a diamondprincess-cut engagement ring - what to know before buying a diamond

Before Buying a Diamond: 9 Tips You Should Know

You’ll have to make many decisions when you choose a diamond for your engagement ring. Here are nine things you should know before buying a diamond.

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If you're shopping for an engagement ring, you've probably never bought a diamond before, and things can get confusing. Here are nine tips you should know before buying a diamond.
This princess-cut diamond looks stunning in a simple pavé ring. © CustomMade. Used with permission.
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#1: Compromise Carefully

It's no secret that diamonds are expensive. Despite this, first-time buyers often find diamonds are pricier than they initially expected. So, before buying a diamond, review your finances and set a budget. Then, take a look at diamond prices to see what you can afford.

If you get sticker shock, you might decide to compromise on the diamond of your dreams.

However, compromising doesn't mean you should just buy a bargain-priced diamond. In truth, there are no good deals in diamonds. There are fair deals, but if it seems like a diamond is priced lower than the rest, there's a reason for it.

You'll get a better diamond if you opt for a lower carat weight than if you buy a diamond that seems like a "good deal" when compared to other diamonds of a similar weight. You can still get the ring of your dreams, if you compromise a bit on stone size instead of quality.

#2: Consider Alternatives Before Buying a Mined Diamond

There are plenty of alternatives to mined diamonds that can make excellent engagement ring stones. For example, lab-made diamonds are becoming more popular. While these have the same beauty and durability as any diamonds, they cost about 30% less than mined diamonds of similar quality.

Three-stone platinum engagement ring from James Allen with a lab-created diamond center stone, 1.20 cts. F color, VS1 clarity, ideal round cut.
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at James Allen

While diamonds are "traditional" engagement ring stones, colored gems are often durable enough for daily wear and absolutely beautiful in their own right. Sapphire, ruby, and emerald are the most popular, but gems like morganite and aquamarine also make great ring stones.

white gold engagement ring with sapphire center stone
14k white gold engagement ring with a sapphire center stone and two diamond side stones. You can also get something similar at CustomMade. Photo courtesy of and Hampton Estate Auction.

#3: Cut Quality is King When You're Buying a Diamond

A diamond should come with a grading report from a reputable laboratory like the Gemological Institute of America (GIA) or American Gem Society (AGS). This report will contain a lot of details, but the easiest way to assess a stone's quality is by reviewing the Four Cs: cut, clarity, color, and carat. Of course, you'll still need to examine the diamond closely, but these grades will be your first indication of the diamond's quality.

For a diamond, the most important of the Four Cs is the cut. A well-cut diamond will make color and clarity imperfections less noticeable. Since a well-cut diamond will look brighter, it will also appear larger than its carat size.

So, when you're diamond shopping, keep your standards for cut quality high.

#4: Diamonds Come in Many Shapes

Although most consumers prefer round diamonds, there are many different diamond shapes, and some non-round shapes will really stand out from the crowd. They're also available at a discount compared to round diamonds.

Most of these non-round shapes actually appear larger than rounds of the same carat weight. That's because they have an elongated shape or a diagonal length that makes them look bigger.

14k yellow gold solitaire engagement ring from James Allen with a heart-cut diamond, 1.60 cts, J color, VS2 clarity.
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at James Allen

After the round, the second-most popular diamond shape is the square princess cut. Oval and pear shapes are currently quite popular, too. If you're considering a shape other than round, check out our shape-specific guides:

PrincessCushionOvalEmeraldPearAsscherMarquiseRadiantTrillionHeartOld European Cut

#5: Carats Influence Price More Than Appearance

Carat weight has a major effect on diamond pricing. That's because diamond prices-per-carat go up at certain so-called "magic numbers" or benchmark carat sizes: 0.50 cts, 1.00 cts, 1.50 cts, 2.00 cts, 3.00 cts, 4.00 cts, and 5.00 cts.

Let's say a 0.50-ct diamond of a particular quality costs $3,600 per carat. That means the stone costs $1,800. You might assume that a full-carat diamond of the same quality would cost $3,600. In fact, at the one-carat benchmark, this diamond has a price-per-carat of $7,000, so it would cost $7,000.

Diamond prices go up exponentially as carat weight increases. A 2-ct diamond of this quality would cost $27,000, not $14,000, and has a price-per-carat of $13,500!

However, the face-up size of a diamond doesn't increase in the same way. In fact, the face-up area of a half-carat diamond is more than half that of a one-carat diamond. So, dropping to a lower carat weight has a bigger impact on price than it does on appearance.

  • before buying a diamond - 1 ct
    1.00-ct round diamond from James Allen, G color, VS1 clarity, good cut.
  • before buying a diamond - 0.50 ct
    0.50-ct round diamond from James Allen, G color, VS1 clarity, good cut.

    Both these diamonds from James Allen have G color, VS1 clarity, and good round cuts. However, the 1.00-ct stone costs $5,450. The 0.50-ct stone costs $1,170. 

    #6: Keep Color and Clarity Simple

    Although color and clarity have grading scales, we recommend thinking of these diamond properties in terms of "good" or "not good." For color, either the diamond will appear colorless or it won't. For clarity, either the diamond will appear flawless to the eye, "eye-clean," or it won't.

    With this approach, you won't pay too much for color or clarity grades that your eye can't distinguish. There's no reason to pay more for a D color diamond if you can't tell the difference between D and H. And there's no reason to pay extra for a diamond with Flawless (F) clarity when most SI1 diamonds will appear flawless, too.

    • 1.30-ct, D color, F clarity round
      1.30-ct diamond, D color, F clarity, excellent round cut.
    • 1.30-ct, H color, SI1 clarity round
      1.30-ct diamond, H color, SI1 clarity, excellent round cut.

      Both these diamonds from James Allen weigh 1.30 cts and have excellent round cuts. One has D color and F clarity and costs $19,290. The other has H color and SI1 clarity and costs $7,440. Can you distinguish these stones based on their color? At 20X magnification, you can see the SI1 stone has a light-colored flaw near the center of its table. However, if you use the magnification tools on the James Allen site to zoom out to a normal viewing distance, the stone will appear eye-clean.

      #7: Consider the Ring Style

      When shopping for engagement rings, many consumers worry more about center diamonds than any other aspect of the ring. No one will argue that the diamond is unimportant, but having a ring design that fits your style and personality makes a big difference on how you'll feel about your ring. The ring itself will also affect your diamond's appearance. Everything from the setting to metal color — white, yellow, or rose — will play a role.

      So, take the time to consider what kind of setting you'd prefer: plain, intricate, or something in between. Many people love the look of a band paved with diamonds. Others prefer a simple halo setting. Minimalists and traditionalists might prefer a solitaire setting. Some might want a design with extra sparkle.

      Pick the design that will make you and your partner happiest. Consult our in-depth guide to engagement ring settings or try browsing online through all the different setting styles available at James Allen.

      #8: Do Your Research Before Buying a Diamond

      Doing your research before you buy anything is always a good idea. If you're spending thousands on an engagement ring, you want to know that it will look good and you're not paying too much for quality that you won't ever notice.

      However, many different factors influence diamond quality. No matter how much research you do, there's no way to become an expert without years of training. Of course, you don't have to be an expert to know what looks good. If you follow our recommendations, you're sure to find a nice diamond.

      #9: Always, Always, See Before You Buy

      For first-time diamond buyers, the key to being happy with your purchase is to find one that just looks good. Without actually seeing the diamond perform, you won't know if it's a keeper or a dud. Therefore, where you buy your diamond is important.

      If you're shopping at a brick-and-mortar jewelry store, you'll be able to examine your stone easily. Make sure the jeweler shows you the diamond under magnification in its intended setting as well as from different angles.

      If you're buying online, you still must see your diamond before you buy. Both James Allen and Blue Nile offer videos of their diamonds and online magnification tools. As two of the largest suppliers, they have great selections and prices to fit any budget.

      Going custom is another great option. CustomMade is a fully-online custom jeweler that specializes in creating an engagement ring that will fit your style and personality perfectly. Plus, their experts can make sure you get the best diamond you can afford.

      Addison Rice

      A geologist, environmental engineer and Caltech graduate, Addison’s interest in the mesmerizing and beautiful results of earth’s geological processes began in her elementary school’s environmental club. When she isn’t writing about gems and minerals, Addison spends winters studying ancient climates in Iceland and summers hiking the Colorado Rockies.

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