A Thorough Guide to the Bow-Tie Effect (With Animation + Buying Advice)

The bow-tie effect: classy or problematic?

The 4Cs identify most imperfections within a diamond, but there are a few other characteristics to look out for when buying a new gemstone. One of these features is the bow-tie effect, which can create a dark blemish in certain fancy diamond shapes. Although bow-ties may be hard to spot with an untrained eye, understanding what to look for can make the difference between a visible bow-tie and a sparkly diamond.  

In this article, we’ll cover:

• What is the bow-tie effect?
• How does it impact a diamond’s value?
• How to identify the bow-tie effect and choose a quality diamond.

What is the bow-tie effect?

When looking at a diamond, you may see a darker, bow-tie shaped space across the center of the table.  This is a result of the bow-tie effect, and it’s directly related to the diamond’s cut. The bow-tie effect can impact diamonds of all cut grades, but the cutting process can determine how much it will affect a gem’s shine.

What causes the bow-tie effect in diamonds? Which shapes are affected?

Light refracting through the facets of a diamond creates fire and brilliance, giving us that mirror-like sparkle we crave. When a facet is not cut properly—due to an inclusion or poor technique—it does not interact with light in a way that produces reflection. As such, the facet appears dark when viewed through the table of a diamond. With the bow-tie effect, specific facets suffer this lack of refraction, causing the bow-tie shape at the center of a diamond.

Unlike many common diamond issues, the bow-tie effect is a result of light blockage rather than light leakage.💡 Light does not properly interact with the incriminating facets, even when the stone is turned or moved.  

Is the bow-tie effect graded?

There is no precise grading for the bow-tie effect, but gemologists use a general scale to explain the severity of a diamond’s bow-tie. The categories are as follows:

Grade	Definition
Slight	The bow-tie is a faint gray, and it covers a tiny surface area.
Noticeable	The bow-tie is a dark gray and spans a mid-sized surface area.
Obvious	The bow-tie is black or extremely dark and covers a large surface area.

As previously stated, the categories are not incredibly defined, but understanding where a diamond’s bow-tie effect falls on the scale can help you shop smarter.

How does the bow-tie effect impact a diamond’s value?

Is the bow-tie effect a flaw or feature?

So, is the bow-tie effect a flaw created by a low-quality cut? Or, is it just another feature of certain diamond cuts? Because the bow-tie effect is not a quality you can find on a diamond report, it can be tricky to pinpoint how much a bow-tie affects a stone’s value. Additionally, some buyers like the bow-tie look, and so the inherent value of diamonds with the effect increases for these individuals.

Does the bow-tie effect impact a diamond’s GIA grade or report?

Overall, while bow-ties may be more visible in lower quality cut diamonds, they can appear in any stone, as the GIA does not have a specific criterion for grading them.

In fact, you will not find any notes on a diamond’s bow-tie in your GIA report. That is because a bow-tie’s effect on a diamond’s value is too subjective: some will like it, some will not. Focusing on the 4Cs, researching a diamond’s characteristics in its grading report, and visually inspecting a diamond are the best tactics for avoiding a bow-tie.

Can diamond cutters eliminate the bow-tie effect?

Although it’s easy to assume an experienced gem cutter could cut around such an imperfection, it’s really not that simple.💡 Even expert gem cutters struggle to balance the demands of cutting perfect stones, and situations must be weighed individually.

For instance, if removing the issue that causes the bow-tie effect would shave too much carat weight off of the uncut diamond, a cutter may opt to avoid losing carat value and cut with the issue intact. Or, if there are larger inclusions that could cause more noticeable problems within the uncut gem, a cutter may choose to eliminate those areas at the cost of cutting a stone with a bow-tie. Trying to eliminate a bow-tie can result in cuts that are too deep, shallow, or wide, affecting the gem’s overall sparkle.

How to identify the bow-tie effect in diamonds

Here are a few suggestions to spotting the bow-tie effect in your selected gemstone:

Inspect the diamond at a local jeweler

If you’re shopping for diamonds in a brick-and-mortar location, make sure you thoroughly examine your gems. Since you can’t find information regarding the bow-tie effect in your diamond’s grading report, carefully observe your stone in as many settings as possible while at the store.

Inspect your diamond in different lighting, under a jeweler’s loupe, by rotating the diamond, etc. You can also observe the colors of light the stone is emitting to identify obstructions. Flashes of red and green indicate a quality cut, but if you see too much blue light across your diamond’s surface you may want to inspect it more closely.

Whatever it takes, make sure you physically appraise the gem, and ask your jeweler questions if you’re not sure. Jewelers are typically happy to help, and they can guide you to a set of stones that have as little or as much bow-tie effect as you want.

Use the videos and photos provided by retailers online

If you’re purchasing your diamond online, take advantage of the revolutionary tools offered to observe diamonds online. Never buy a diamond sight unseen!

There are plenty of online retailers that provide full, 360° imaging and videos so you can properly examine your diamond’s scintillation. Two major online shops that offer this tool are James Allen and Blue Nile.

At James Allen, the 360° video technology makes spotting a bow-tie much easier. Although the video itself spins the diamond for a full view, you can also click the image and drag left or right for a slower, more precise look. You can also zoom in and out to see how the diamond will look both up close and from a distance, so you can see how a bow-tie may show once the diamond is in a setting.

If you’re still not sure about a diamond, consider consulting an expert with James Allen’s Real-Time Diamond Inspection service. Doing so allows you to speak to a seasoned diamond professional right away, so they can provide in-depth observations regarding your chosen gem. It also gives you peace of mind that what you are seeing or not seeing is valid!

Blue Nile also uses 360° video technology so you can view your diamond from all angles. Similar to James Allen, you can slow down the video by dragging the image either left or right. Blue Nile also allows you to compare diamonds alongside each other for further inspection. This can be incredibly helpful if you’re unsure which diamond has a larger bow-tie, or if it has one at all.

How to choose diamonds with the bow-tie effect

So how can you make sure you buy the diamond that’s right for you, with or without a bow-tie? Here are some recommended tips for purchasing diamonds that may experience the bow-tie effect:

Remember what the bow-tie effect entails

Don’t forget that the bow-tie effect is not always a negative feature, but it does mean there is a light blockage within a diamond. Understanding what the bow-tie effect is can help you decide whether the feature is something that will bother you. Also, keep in mind the diamond shapes that typically suffer from the bow-tie effect: pears, hearts, ovals, and marquise.

If you’re interested in any of these shapes, it’s important to keep the bow-tie effect in mind while shopping.

Balance the bow-tie effect and the 4Cs

While a strong bow-tie effect may seem like a dealbreaker, it’s important to consider all of the 4Cs in your diamond buying decisions. The 4Cs are the true markers of a diamond’s quality, and they dictate price and value over time. Make sure you understand what you want in a diamond and which qualities matter most to you before focusing on the bow-tie effect.

Diamond buying is a personal decision, as each buyer seeks something different from their chosen gem!

View diamonds from every angle

Find a jeweler that you trust that will allow you to carefully examine any diamonds you are interested in. Try different lighting, positions, and more to get a full view of all of your diamonds' features and identify the intensity of the bow-tie effect in each. If you’re buying online, take advantage of video technology to observe every facet of your diamond. Never buy a diamond without seeing it first!

Compare your chosen diamond with other diamonds

Whether buying online or in a store, take some time to compare your diamond to others. Even if you’re only interested in one, it can be helpful to see how your chosen stone looks in a lineup of comparable diamonds. Doing so allows you to compare its bow-tie, color, and other factors relative to other gemstones.

The bow-tie effect: A personal choice

As previously stated, the bow-tie effect isn’t necessarily a negative characteristic. Many people enjoy the sleek, classy look of the bow-tie within their diamond, and it provides a level of character for those who feel diamonds all tend to look alike. However, avoiding diamonds with large bow-ties that affect sparkle is still recommended!

Now that you know what to look for, you can successfully ask your jeweler the right questions and find the right fancy-shaped diamond for you. You can also read our cut article to learn more about how a diamond’s cut affects its brilliance.