Diamond Price Guide: Getting the Most Value in Natural and Lab-Grown Diamonds

Diamonds have been a treasured gemstone throughout history and the most popular gemstone for engagement rings in modern times. But determining the price for these rare stones that preserve their value over time may seem a bit mysterious. Most often, the standard wisdom is that diamond prices are based on the 4Cs of color, clarity, cut, and carat weight. In the big picture though, that’s usually just the start of the process to determine the value and price of a diamond.

Adding to that, lab-grown diamonds have become an extremely appealing alternative for sustainability and affordability. However, they have different guidelines for determining value and price. So we’ve gathered our best information and advice in our Diamond Price Guide to break down an insider’s perspective on diamond price, value, and quality with some money-saving tips throughout.

Understanding Diamond Prices

The diamond 4Cs are a starting point for valuing a diamond. To establish a baseline price, Industry dealers use carat, color, and clarity in conjunction with the Rapaport List - an international benchmark used by dealers to set diamond prices in all major markets that is updated weekly.

How the final value of a diamond deviates from this baseline depends on a number of less quantifiable factors such as overall brilliance and brightness, absolute clarity, absolute color, and fluorescence. For example, not all SI1 clarity diamonds are equal; a blemish in the center of a diamond is less desirable than a blemish on the side, even though both are graded the same. Likewise for color, two stones may have the same color grade from the side because that’s how they’re graded, but facing up they may look different.

Let’s consider the following scenario. Say that you’re looking at thirteen natural diamonds all identical on paper as 1.20ct, G color, SI1 clarity, and Excellent grade for cut, polish, and symmetry as certified by the GIA. While seemingly identical, these stones currently trade between $6,375 to $10,125. This is a staggering difference, and as the diamond gets larger, this price swing is even more dramatic. Some possibilities for the difference in this instance could be that the lower price stone is a bad SI1 clarity, looks hazy in person, or has very strong fluorescence.

To further illustrate, here is a picture of a 1.20ct, G color, SI1 clarity diamond priced at $6,781

Now, compare that to another GIA certified, 1.20ct, G color, SI1 clarity, triple Excellent diamond selling for $7,595

The first stone has an obvious black inclusion in the center which would probably be visible to the naked eye. The second stone is much cleaner and looks to have a higher clarity than even some VS2 clarity grade diamonds exhibit.

As we will say a lot in this article, the best way to understand price is to compare stones and see different options side by side in person whenever possible. This is the most reliable way to appreciate subtle differences from stone to stone and how different quality attributes affect price.

Diamond Attributes Affecting Value and Price

The better discussion to have when thinking about a diamond’s value and price is a full consideration of the quality. The quality of a diamond factors in all the other specific characteristics of a diamond not included on the price list.

How you feel about and rank each of these attributes will help guide you to your perfect diamond.

1. Cut Quality

The quality of the diamond’s cut is often considered to be the top consideration for value. When we talk about the cut, or the make of a stone, we are referring to how brilliant a stone looks. A well-cut diamond should look lively and have lots of fire. If a diamond is poorly cut, that then affects the overall appearance and the final value. A master cutter will weigh the finer points of a diamond before deciding on the best cut for its shape. That means determining what will give the diamond a beautiful appearance while retaining size and structural integrity.

The cut rating comes from a predetermined set of numbers that are subject to change but fairly well known in the trade. When a diamond is cut to these very specifications, they may or may not look nice. Nonetheless, it will get an Excellent rating because that is what the system has identified for that grade.

It’s a solid filtering tool for weeding out the bad stones, but it is far from perfect. Brightness, scintillation, and fire are not taken into account specifically, but in theory, an Excellent cut diamond should excel at all three features. This is why we suggest the most important factor to remember about cut quality is to let your impression for what is the prettiest stone to you be the deciding factor.

2. Certificate

A diamond’s certificate proves the legitimacy of the diamond and verifies the attributes you’re seeing in the stone. We can help you interpret everything the certificate says, but not all labs are created equal. Our choice are GIA certified diamonds due to their specific and highly consistent standards for grading diamonds.

For lab-grown diamonds, IGI is the dominant choice for certifications. While not as consistent and strident in their procedures, the IGI is the most reputable choice for lab-grown diamond certifications as the GIA does not offer detailed grading on the lab diamond certificates. Learn much more about diamond certificates and which labs are trustworthy in our Diamond Certification article.

3. Size

The size of a diamond is another component where many consumers get confused. Most people assume that a 1 carat diamond must be bigger than a 0.95 carat diamond. Wrong. Carat is a weight measurement, so if a diamond is cut particularly deep, the face of the diamond will look much smaller than a comparable weighted diamond with less depth. So why not cut a diamond flat like a pancake? Because then the diamond would lose light refraction, and therefore brilliance. So somewhere in the middle; not too flat, and not too deep is the ideal balance of size and brilliance.

Another example is shopping across different shapes - An average 1ct round diamond is about 6.4mm in size, and an average 1ct cushion diamond is about 5.7x5.7mm in size. If these two stones were placed next to each other, the 1ct cushion would look substantially smaller than the 1ct round. This is because cushion cuts retain a lot more weight at the bottom and at its corners, hence why they cost so much less.

The lesson here is that you should shop by “overall look", not carat weight. Also consider the design first before you dive too deep into diamond shopping. The last thing that you want is to spend months researching and finding the best round diamond, only to realize that what you really love is a cushion cut design ring. Focusing on the overall look of the diamond will always be a more beneficial and rewarding route than getting stuck on a carat weight. One tip on saving money is by shopping just under a common weight threshold, such as purchasing a 0.9ct diamond instead of a 1ct diamond.

Take this example of two stones practically identical in look. The data was pulled from our loose diamonds tool:

All of these diamonds are 1.5 carats

One has a 6.30mm diameter, and the larger stone is only one tenth of a millimeter bigger. These two stones currently trade at more than a 25% difference in price simply due to supply and demand, and the psychology behind buying a full carat diamond.

Price per carat changes between weight steps or weight classes and increases exponentially. The weight steps that have a larger effect on the price per carat are the following: 0.50ct, 0.75ct, 1.00ct, 1.25ct, 1.50ct, 1.75ct, 2ct, and so on with each full quarter carat increase. To save money, you can shop just under a weight class. For example, choosing a 0.95ct over a 1ct, or a 1.90ct instead of a 2ct diamond.

4. Diamond Specs

Just as carat weight can be deceiving, color is not always as objective as you think either. A G color diamond isn’t always more colorless and brighter than a H color diamond. A H color diamond with nice medium fluorescence can look brighter and cost much less than a G color diamond with no fluorescence. The best way to do these comparisons and determine the best value for you is to see the options side by side. We encourage you to decide on a budget, keep an open mind on grading specs, and then let your eyes determine the most attractive diamond for your budget.

5. Setting

The setting is how you want to showcase your diamond. It has the ability to enhance all the beautiful attributes of your diamond and present your diamond in the best way. It’s also your diamond’s home and an extension of how you choose to protect its quality and value.

Clients usually want to choose an engagement ring setting as special and unique as the diamond they’ve chosen. We work with all of our clients to provide top quality craftsmanship, expert service, inspired design, and post-purchase warranty that instills confidence in their selection.

6. Fluorescence

Diamond fluorescence refers to the bluish glow some diamonds exhibit under ultraviolet (UV) light. The textbook thinking on fluorescence is that it is a flaw, but we believe there’s nuance to consider with fluorescence.

Most of the time, fluorescence is invisible in daylight. In fact, GIA research has shown that certified diamond graders cannot perceive fluorescence without a black light. Also, for the average observer, none were able to recognize any blue fluorescence when presented with diamonds known to fluoresce.

Furthermore, some fluorescence actually enhances the look of the diamond by making it appear brighter. In the industry, this is often called good fluorescence. Not only can good fluorescence make the diamond look brighter, it can also improve visible color. Since most color in a diamond is yellowish in nature, a blue fluorescence will cancel that out resulting in a more colorless appearance.

So for example, a K color diamond with good medium fluorescence can make the diamond look just as white/colorless as a G or H color diamond. We think that makes this a perfect combination because you pay for a K color diamond, but get the look of a G color diamond.

And as a final note on fluorescence, lab-grown diamonds (other than fancy color lab-grown diamonds) never have fluorescence. We think in time this fact could make fluorescence in a natural diamond a more desirable and valuable trait since it serves as a natural differentiator to lab-grown diamonds.

Our Step-by-Step Guide for Choosing the Prettiest Stone at a Fair Price

Our advice to all clients is to let research be research - it’s a necessary foundation so you can approach a very important decision from a knowledgeable perspective. But once you feel confident in that knowledge, the look of the diamond and the feeling you get from it should be your guide.

To help our clients confidently reach their decision, we follow a tried and true process that helps our client choose a diamond they love.

1. First, we identify basic criteria as a jumping off point. That will include information about minimum or maximum size, budget, desired shapes, or any other specs that are important to the client.

2. Then, we’ll bring out the best options to meet that criteria, as well as some that deviate slightly from the client's stated goals. Most of the time, this will be the best stone: colorless, flawless to the naked eye, and the biggest stone for the budget.

3. We’ll present our selection to the client, and without revealing the lab specs (so as to not prejudice their opinion), ask the client to tell us what they see. Often they will observe that one is the biggest, or that they all look very similar but one in particular seems to have more sparkle and perhaps a slight bit more color.

4. With their observations, we can establish a top one or two favorite diamonds, and perhaps even one the client dislikes. To help make the final decision, we’ll ask "how much more would you pay for the #1 stone over the #2 stone?".

This question helps to establish value and how different in quality the client really feels the stones range. Because while the first stone looks the nicest, it may only look slightly better than the second stone in a value comparison. If stone #1 is priced far outside the additional perceived value, then it may be a sign that it is overpriced for you.

And what if all the stones look exactly the same? Well simple, if they all look the same and there is nothing technically wrong with any of the options, then our advice is to choose the least expensive stone.

This exercise helps to alleviate the feeling of overwhelm that can come from all the considerations about diamond quality, value, and price. When we start with basic guidelines that feel good to the client and reveal what else will be the most important along the way, the truly perfect stone is revealed.

An Important Note About Lab-Grown Diamonds

Lab-grown diamonds have become an extremely attractive option in recent years given their perfect substitutability. Lab-grown and mined diamonds have the exact same composition; they look the same, and have the same durability. Customers who find no value in a product that is mined from the ground and just want a diamond for the look and durability will find lots to like about lab-grown diamonds.

When comparing natural vs. lab diamond prices, you’ll see at least a 45% discount for lab-grown to mined diamonds. That can even go up to 70% if we are comparing high color and high clarity stones.

One drawback for lab-grown diamonds is the supply. It is still much more limited compared to natural mined diamonds. For example, some fancy shapes such as marquise or pear are in extremely short supply. Additional flexibility and patience may be required to find the stone of your choice.

The most commonly cited concern or question about lab grown diamonds is their ability to act as a store of value over time. The answer depends on future supply and demand, and given lab grown diamonds’ short history, there is no way to know where prices are headed in ten or twenty years. That said, what many consumers are finding is that lab grown diamonds offer substantially more for their money compared to natural mined diamonds, so from a consumption perspective (ie. What’s the best option for me now? Or I don’t intend on ever selling this stone) lab grown diamonds represent a very attractive option.

The bottom line for diamond price is that it only speaks to some components of a diamond’s quality and value. As with all the customized pieces we craft, the end goal is always to focus on a truly unique product that you can happily call your own.