February 2020 - Service Jewelry & Repair | Blog

Diamonds, Education

The 4C’s: Carat Weight

February 19, 2020

Carat weight might be the most obvious and straight-forward feature of diamond grading. The metric carat is simply the special unit of weight for diamonds and gemstones, and 1 carat equates to 0.200 gram or 0.007 ounce. Diamond grades are as precise as possible when it comes to carat weight, so let’s take a look at what this process entails and how to understand specific weights.

Carats & Points

Diamonds are often so tiny and light-weight that even the metric carat has to be subdivided to produce a precise measurement. That’s why you’ll usually see carat weight expressed as a decimal, like 0.25ct or 1.55ct, but you may also come across something called points. One point (pt) is equal to 0.1 carat (ct).

100 points = 1 carat

Points and decimals allow these tiny gems to be weighed super accurately, but you might also see carat weight expressed as a fraction, like 9/10ct or 3/8ct. However, it’s important to note that fractions are often less precise measurements. Typically, the fraction is actually referring to a range of weights rather than a specific measurement, so a diamond marked 9/10ct might actually weigh 0.90-0.95ct. If you come across a fraction weight, think of it as approximate rather than exact.

You can use the interactive tool below to see how carat weights compare!

How Diamonds are Weighed

Electronic scales are the most accurate tools for measuring gem weight. The best are so precise that they can weigh a diamond all the way down to .001ct (or 1/10 point)! Once an unset diamond is placed on the scale, its weight is read digitally in an instant. From there, the diamond’s weight might be recorded exactly as it is, or it may be rounded up or down to the nearest point (or 1/100ct).

For example, let’s say the scale reads 1.004ct. A diamond grader might record the weight as is, or they might take that number and round it down, labeling the diamond as 1.00ct. Similarly, a diamond which weighs 0.995ct might actually be rounded up, labeling it 1.00ct as well.

Rounding the weight might seem counterproductive or even imprecise, but even when rounded, diamond weights are accurate to 35 millionths of an ounce! Rest assured that rounding such tiny amounts up or down does not significantly impact a diamond’s final value.

How Weight Affects Value

For diamonds, pricing isn’t as straightforward as other things sold by weight. For example, let’s say the price of gold is $1000 per ounce. No matter how many ounces of gold you want to buy, you can just multiply your amount by the per ounce price. So, if you wanted a three ounce bar of gold, you could expect to pay $3000. This is not the case for diamonds!

When it comes to diamonds, value is all about rarity. So, let’s say you’re looking at a 0.50ct diamond priced at $1,500. Based on that price, you might assume that a 1.00ct diamond of comparable quality would cost you $3000. However, a 1.00ct diamond will actually cost up to 4 times more than a 0.50ct diamond!

Why? Because a 1.00ct diamond is much more rare than a 0.50ct diamond, and sizes over 1.00ct only get rarer!

Putting It All Together

When you’re on the hunt for a diamond, you’ll come across many different stones of the same carat weight and cut style, yet they’ll likely be priced differently. Let’s say you’re looking at two round brilliant 1.00ct diamonds, one priced at $3000 and the other $2000. If you’ve made it this far in our blog series, you’ll have a good idea why! Put simply, the higher priced diamond is more rare.

Now, based on that, you might assume that all comparable diamonds of the same weight will cost about the same—but they don’t! Believe it or not, a princess cut diamond with the same grade and weight as a round brilliant diamond will actually cost up to 25% less! That’s because all factors of the 4C’s come together to produce a diamond’s final value, and a princess cut simply costs less to produce. On the flip-side, that means you can get a larger princess cut diamond for the same price as a smaller round brilliant!

When it comes to diamond color, you might find that a 1.00ct natural blue diamond is much more expensive than a 1.00ct white diamond—even if the blue diamond is graded lower in cut and clarity! Why? Because it’s rare enough to find a naturally blue diamond at all—let alone one that weighs 1.00ct after being cut! By the same token, you might find a 1.00ct color-enhanced blue diamond that’s actually less expensive than a 1.00ct white diamond of the same clarity.

As you can see, each of the 4C’s can raise or lower a diamond’s value in unique ways, and now you know why! If you missed our other posts on clarity, color, and cut, check them out for more details on how each factor affects value.

If you still have questions, we’d love to help you further! Why not send us a message or pop into one of our stores?

You can also browse our extensive collection of diamonds and diamond jewelry right here on our website!

We hope to serve you soon!

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Diamonds, Education

The 4C’s: Clarity

February 12, 2020
Today, we’re going to dive into another part of the 4C’s: clarity. In this context, clarity is defined as “a diamond’s freedom from blemishes and inclusions.” The more free the stone is, the higher the final value will be. Let’s take a look at what these clarity characteristics are and how they’re judged.

Blemishes

Put simply, blemishes are irregularities on a diamond’s surface. Sometimes, blemishes are a perfectly natural part of a diamond’s formation within the earth. For example, irregularities in the diamond’s crystal structure can cause a grainy texture to occur.

Most blemishes, however, are the result of human contact with the stone. Nicks and pits can be formed when a diamond is struck against something, while scratches and abrasions can occur when two diamonds rub up against each other. Similarly, a poor polishing or cutting job can accidentally leave blemishes too.

Believe it or not, some blemishes are actually added on purpose—in order to enhance the appearance of the stone! For example, a diamond cutter might add extra facets, which can actually remove more obvious blemishes. Nonetheless, extra facets are technically considered to be blemishes, too, since they’re surface irregularities.

Inclusions

Inclusions are irregularities inside the diamond. More often than not, inclusions occur as a natural diamond is formed within the earth, but human contact can sometimes create them too.

As far as natural inclusions go, the diamond’s crystal structure or trapped impurities are the most likely causes. Inside the earth, a forming diamond is subjected to unbelievable pressure and comes into contact with all sorts of other elements. An irregular crystal structure can make a diamond look cloudy, grainy or even colored. Likewise, little bits of carbon or other elements can become trapped inside, causing dark or colored spots to appear.

On the other hand, accidental blows or a poor cutting job are usually responsible for human-created inclusions. These mishaps can cause bruises, chips, and fractures. However, just like extra facets, a purposeful inclusion can sometimes mask or eliminate other inclusions. An example of this technique is laser drilling, which can dramatically lessen the appearance of dark spots within the diamond. Nonetheless, the drilling process leaves a tiny channel behind, which counts as an inclusion of its own.

Evaluating Clarity

A jeweler’s loupe, like the one pictured above, is often used to evaluate diamonds

A skilled diamond grader uses both the naked eye and powerful magnification to observe and note clarity characteristics. If an inclusion or blemish can be seen with the naked eye, it will have the greatest affect on value. Nonetheless, even microscopic irregularities can impact appearance and durability, so diamonds are inspected under 10x magnification.

During this process, there are five main factors a grader is considering:
1. Size: the larger the characteristic, the more visible it will be.
2. Number: the more numerous, the more obvious.
3. Nature: is it an inclusion or a blemish? Inclusions are usually considered more important than blemishes.
4. Position: where is the characteristic located? For example, a diamond’s reflective properties can make one inclusion look like many, while an inclusion on the edge might not be very noticeable at all.
5. Color: most characteristics are white or clear, but some can be colored or dark. This is known as relief.
Even though the diamond is examined at all angles, whatever is visible face-up will be the most important. However, it’s important to keep in mind that the grader isn’t thinking about aesthetics alone. Diamonds may be the toughest material on earth, but they can still suffer damage. When fractures and cavities are graded—especially if they’re large—the future durability of the diamond is considered.

GIA Clarity Scale

After all the clarity characteristics are observed and documented, the actual grade is assigned. The more effect they have on durability and appearance, the lower the final grade will be. There are eleven possible grades, ranging from Flawless (FL) to Included (I₁). Check out the interactive tool below to see examples of each!

The Bottom Line

It’s always important to remember that diamond grades are highly technical and not an “objective” standard of beauty. When a diamond is graded Flawless and earns a hefty price tag, it’s ultimately about rarity.

Believe it or not, only about 2% of gem quality diamonds earn the official Flawless grade. In fact, most diamonds found in stores today are between VS and SI, yet most people would think they’re Flawless!

As you’ve learned today, inclusions and blemishes can be quite natural and completely invisible to the naked eye. Yet, even when they’re intentional, accidental or quite prominent, they aren’t necessarily undesirable. It all comes down to personal preferences.

For some, a Flawless diamond created in the lab or by mother nature might be the pinnacle of beauty. For others, a diamond with a unique pattern of dots or lines will feel one-of-a-kind and truly special—indeed, it is one-of-a-kind, as no two diamonds are alike!

If you missed our other posts about the 4C’s, be sure to read how cut and color are graded too! If you have any questions about the 4C’s or diamonds in general, we’d love to help you further. Why not contact us or pop into one of our stores? You can also browse our extensive collection of diamonds right here on our website!

We hope to serve you soon!
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Diamonds, Education

The 4C’s: Color

February 5, 2020

When you hear the word “diamond,” what’s the first image that comes to mind? If you’re like most people, you might imagine a dazzling colorless gemstone—but did you know that truly colorless diamonds are extremely rare? Not only do most diamonds have a tint, but they can be vividly colored too! Today we’ll take at the look at how a diamond’s color is graded as part of the 4C’s.

The Normal Range

Most diamonds fall within the colorless to yellow, brown or gray range – GIA.edu

While diamonds can be any color of the rainbow and more, most fall within a certain spectrum. The vast majority of diamonds available today range from colorless to light yellow, brown or gray. You can think of this spectrum as the “normal range.”

Trace elements—like nitrogen or boron—that enter the diamond as it forms are mostly responsible for this range of color, but the stone’s crystal structure can also play a role. When intense pressure distorts a diamond’s crystal structure, hues like brown, pink, red and purple can appear. It’s only when a diamond’s chemical and crystal composition are close to perfect that colorlessness results. Otherwise, at least a faint tint will be detectable.

The GIA normal range color scale

The Gemological Institute of America (GIA) has developed the most popular grading system in the US, so we’re going to use their scale.

For diamonds in the normal color range, an alphabetical spectrum from D (colorless) to Z (light yellow, brown or gray) is used. However, these letters don’t actually refer to specific colors. Instead, they simply mean that the diamond falls within a precise range of color. Therefore, two diamonds which are both graded H can actually look a bit different from each other.

Nonetheless, these grades are very technical. In fact, it’s typically only the experts who can tell a D diamond from an H diamond when it’s mounted in jewelry. Indeed, even diamonds graded K, L or M will usually appear quite colorless if they’re under 0.5ct.

When it comes to this scale, you can typically expect a diamond’s value to correlate with how colorless it is. The closer a diamond gets to a D grade, the more valuable it will be. However, when a diamond is graded below a Z, that’s no longer true. In fact, these special diamonds are valued for their color—not their lack of it! Let’s take a look at them next.

Fancy Color

Check out these blue, yellow, aqua and pink fancy color diamonds! – GIA.edu

If a diamond doesn’t fall within the normal range, it’s considered fancy color. This includes black, blue, red, green, vivid yellow and much more. These diamonds are very rare in nature and are valued accordingly. Believe it or not, the entire world only produces a few thousand carats of fancy colors each year! When it comes to grading them, three qualities are considered: hue, tone, and saturation.

Hue is simply the diamond’s color category. These categories can be a single color (like red or blue) or some combination (like reddish-orange or bluish-green). Tone refers to the color’s lightness or darkness, while saturation (sometimes called intensity) is the color’s strength and purity. You can see the interplay between these qualities in the chart below.

The GIA fancy color grading scale

The GIA fancy color scale ranges from faint to fancy deep, but you can’t look to the very top or very bottom of this chart to determine value. Instead, the most valuable grades are found near the middle, with fancy vivid being the most valuable of all. Why? As always, it’s about rarity. Fancy color diamonds with super high saturation and a light to medium tone are extremely hard to find, and their price will always reflect this.

Examples of different yellow diamond grades, ranging from fancy light to fancy vivid – GIA.edu

However, it’s important to note that what these grades actually look like is completely dependent on the stone’s hue. Say you’re comparing two fancy vivid diamonds: one yellow and one blue. You may notice that the blue diamond appears paler and less saturated than the yellow one—yet they have the same grade! Why? Again, it’s all about rarity.

Believe it or not, each hue has it’s own spectrum of possible saturations and tones, so the grading scale is reinterpreted to reflect these differences. It simply wouldn’t make sense to grade blue diamonds by comparing them to how saturated or intense yellow diamonds can be. Instead, they are graded against other blue diamonds—which happen to be much harder to find than yellow ones!

At first, this may seem a bit complicated, but it actually helps to keep things simple! No matter the hue, fancy vivid is like a D rating on the normal range scale—it’s the most valuable simply because it’s the most rare.

If you ever start to get confused, just remember: grading isn’t about ranking how beautiful a given diamond is—a diamond of any hue, tone or saturation can be absolutely breathtaking. It’s all about rarity.

Color Enhancements

Thanks to modern technology, the color of a diamond can sometimes be changed! We won’t get into how this scientific marvel is achieved in this post—you can read our article about diamond treatments here—but these treatments do affect value, and I bet you can guess why. That’s right—we’re talking about rarity!

Though these treatments can make a diamond colorless, black, or practically any color of the rainbow, they will be considered less valuable than their natural counterparts—sometimes the difference in value can be well over 50%! As always, it’s because naturally colored and colorless diamonds are more rare. Nonetheless, these treatments can sometimes increase the value of a diamond well beyond what it would fetch had it not been treated.

If a diamond has undergone any treatments, it will be disclosed on the diamond’s grading report. This makes it easy to understand why two diamonds that look almost identical are valued so differently! Let’s dive into how that report is created.

The Grading Process

So, we’ve seen what the possible grades are, but how are they actually determined? After all, there are so many possible tints and colors, plus so many different conditions under which to view them. That’s why super precise methods have been developed by GIA and other labs around the globe. Even though these methods differ somewhat for the normal range vs. fancy color, they share most of the same steps.

Chiefly, diamonds of any color are graded relative to other diamonds of known color. These are called master stones, because they’re considered the standard for each hue. Master stones make it much easier to determine exactly where a given diamond ranks on the possible color scale.

An example of GIA master stones

Next, the lighting conditions are perfectly controlled. Graders typically work in a rather dark room with a special light source that’s optimized for color perception. Then, both the master stones and the diamond to be graded are turned upside down. Why? Because this minimizes reflections, which can alter the way the color appears.

However, fancy color diamonds are not turned upside down when graded. That’s because the way a diamond is cut can influence the way its color appears too! Therefore, it’s actually more accurate to grade fancy colors face up.

Today, special instruments have been developed to aid in the process of grading, but they’re not 100% accurate. Believe it or not, nothing can quite beat the precision and accuracy of the well-trained human eye—at least for now!

The Bottom Line

Beauty is in the eye of the beholder.

For diamond color, that saying has never been more true. Whether you’d like a rare pink diamond or a colorless classic, it’s all about what you find most alluring. The price, however, is a carefully considered valuation, and now you know how and why!

If you missed our last 4C’s post about cut, why not check it out now and find out how that quality is graded too? Next time, we’ll explain how a diamond’s clarity is graded, so be sure to stay tuned!

In the meantime, why not stop by one of our stores and see our collection of loose diamonds and diamond jewelry up close and personal—even under our microscope! Or, you can view our extensive diamond collection online here and our diamond jewelry here!

We hope to see you soon!

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