By Gary A.
Edited by Brian M.
Published Sep 9, 2021
Edited on Dec 8, 2024
Finding the right balance between size and sparkle, understanding a diamond carat total weight could be the best way to evaluate diamond TW and maximize value in your engagement ring purchase.
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Just when you were starting to feel like you got your head around the four Cs, there’s another mysterious abbreviation you’ve got to work out: CTTW.
While you won’t see it on every piece of diamond jewelry you come across, CTTW is an important and common sight to see, usually included alongside other information about cut, color, and clarity.
Don’t panic – it’s a pretty easy concept once you’re able to recognize what it means for diamond jewelry, and will prove very useful if you’re shopping for pieces that are sold with more than one diamond included. First, you just need to wrap your head around what ct tw in diamonds mean.
CTTW stands for Carat (CT) Total Weight (TW). This might also be expressed as ‘total carat weight’, or under the abbreviation CTW, but it will mean the same thing regardless: the total weight of all diamonds included within a piece of jewelry.
Imagine you have a ring setting that features a pavé band, which included many melee diamonds. Or, alternatively, a halo setting made up of, say, sixteen accent diamonds. The best way for jewelers to summarise that ring is by offering a CTTW, or a carat total weight for that ring, rather than listing the individual carats of each diamond used. This approach is especially useful in semi-mount settings, where the center stone can be chosen separately to create a custom look.
So, the total carat weight of that halo setting could be say, 2.5 carats. If you were to add your 1.5 carat diamond into the center of that ring, the ring would then have a CTTW of 4 carats.
Since a diamond solitaire will only ever feature one diamond, it will only ever offer the carat weight (or CT) of that diamond, rather than a CTTW for the ring.
So, what does TW mean in diamonds? TW simply stands for total weight. It’s just another total carat weight abbreviation.
Sometimes, CTTW will be expressed in fractions. For instance, ¼ CTTW. This would translate to a total carat weight of 0.25 – or 0.05 grams (one quarter of a carat).
The same goes if points are used. A 0.5 point TW will mean that all the diamonds amount to half a carat.
These days, many grooms like to incorporate a little sparkle into their wedding band. If, say, they chose to use the flush setting to incorporate a couple of very small diamonds into the band, then the CTTW of that ring could well be as low as 0.25.
For the same reason that your center diamond’s carat weight is important to know: it will influence the overall value of the ring.
It’s pretty common for first-time shoppers to presume that a piece of diamond jewelry accompanied by the tag ‘CTTW’ is, perhaps, not made of real diamond at all. After all, the abbreviation CZ refers to the somewhat convincing (though definitively inferior and less valuable) Cubic Zirconia, right?
Obviously, when you’re shopping from a trustworthy jeweler, then you don’t need to get caught-up on the idea of being able to ‘outwit’ the seller – but it’s still handy to understand this method for understanding the overall value of the ring, since your jeweler will definitely want to make you aware of it.
Any piece of diamond jewelry that features more than one lone diamond will have a CTTW, whether you’re shopping for a pair of diamond earrings, a pavé infinity ring or, of course, an engagement ring. Jewelers don’t just add these small, accent diamonds into jewelry and guess at the cost – every slight change in carat weight is noted down, and used to determine the item’s value.
Before we dive deeper into the specifics, here are some practical tips to help guide your decision-making process:
Understanding the total carat weight (CTTW) and carat size is crucial when purchasing a diamond engagement ring. Here are key practical tips to consider:
Now that you’ve got these practical tips, use Jeweler AI below to find the perfect engagement ring that suits your style and budget:
By now, you’ve probably gotten used to the concept of carats: representing a weight of 0.2 grams each, they are by far the most commonly used unit of measurement for diamonds. So, as one example, 1.5 carat diamond weighs 0.3 grams, or 300 milligrams.
When you’re buying a loose diamond, this is the only number you need to know. When you’re buying a diamond ring – or any piece of jewelry that features more than one diamond or gemstone – you need to think in terms of the TW of the diamonds.
The value of a 1 CT diamond will not be the same as it is for a collection of diamonds with a CTTW of 1. While, in terms of weight, you’re getting the same ‘amount’ of diamond, larger diamonds are considered far more valuable than smaller diamonds, which are typically created as a ‘byproduct’ during the cutting process for larger diamonds. Big diamonds are impressive status symbols’; while many smaller diamonds elevate the look of a ring and create an incredible sparkle, they still won’t be anywhere near as coveted as a single big diamond of the same TW.
In other words, a 0.1 carat diamond won’t cost a tenth of the price of a 1 carat diamond, which means that a CTTW of 1 won’t cost the same as a single, 1 carat stone. This is the same reason why a 2 carat diamond won’t simply cost doubt what a 1 carat diamond with the same cut, color, and clarity grades. Price increases exponentially.
Focus on the largest stone, as this is where the bulk of the ring’s value will be stored. If you’ve brushed up on your diamond value knowledge, then this won’t be too tricky – just avoid investing in a ring if the carat weight of the large, center stone is not disclosed.
For jewelry that comprises many, many small diamonds but no large center stone – say, a cluster ring – then don’t be lured into paying an unnecessarily high price for diamonds that, individually, have a very low value.
Here’s a concrete example: the pavé band. Each diamond is typically around 0.01 – 0.02 carats, but the total carat weight can vary from a fraction of a carat, to much, much higher. A half-pavé band can feature a handful of melee diamonds under 0.01 carat each, while a full pavé band can be created from many, slightly larger diamonds – any anywhere in between. The value may be below $1,000 in some instances, even if the TW of the diamonds would correspond to a much more valuable single diamond.
While, for the center stone, we’d recommend aiming for a diamond at or above 1 carat in weight, there really is no ‘ideal’ CTTW for the ring itself.
Some of the most beautiful and classic engagement ring styles will have a CTTW of zero before the center diamond is added. This Oval Cathedral Engagement Ring in Yellow Gold, for instance, features only the center stone, and no additional accents within the setting itself. So, say you decided to use this 2 Carat F-VSI Oval Diamond, your ring would have a CTTW of 2.
Then again, some of the most popular and enduring styles feature plenty of small, complementary melee diamonds that will raise the CTTW of the ring considerably. Say you placed that same diamond within this Oval Halo Engagement Ring in Rose Gold; the CTTW of the completed piece may be double that of the first ring – if not more.
An even more extreme example of the different total carat weights engagement rings feature would be the three stone engagement ring setting, like this Three Stone Oval Engagement Ring in Platinum. While this features fewer separate diamonds than the halo, each one will boast a carat weight that will be significantly higher than the previous ring’s accent stones, meaning a potentially higher total carat weight.
Basically, while you’re probably leaning towards one of the rings on this list, there’s no right or wrong total carat weight for any engagement ring. All of these rings are beautiful, and representative of very popular styles among brides-to-be.
The CTTW of your engagement ring matters to its value, not its beauty – or, for that matter, the impact it will have when you finally give it to your future bride.
CTTW is an important concept to get your head around, since you’ll likely run into it a lot as you start researching engagement rings, taking a look at styles and, most importantly, working out what sort of prices the type of rings you like tend to fetch at the jewelry store.
It’s definitely not as important a concept to your engagement ring as the Four Cs, or the design of the setting itself, but it does matter to the overall cost. If you want to lower the cost, then lowering the CTTW (by, for instance switching from a full pavé to a half pavé) is a good place to start, which is why it’s great to feel confident using CTTW in conversation.
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