1 Carat Diamond (1.00ct)
Our Collection
Browse Our 1 Carat Diamonds
Hand-picked certified 1 carat diamonds from our current stock — at prices up to 75% below retail.
Size guide
How Big Is a 1 Carat Diamond?
A well-cut 1.00 carat round brilliant diamond measures approximately 6.5mm in diameter — roughly the width of a standard pencil eraser. This is the benchmark size that most people picture when they think of a diamond engagement ring, and it delivers a strong visual presence on any finger.
It's important to understand that carat measures weight, not physical size. A deeply-cut 1.00ct diamond can appear smaller than a well-proportioned one, because more weight is hidden in the pavilion (bottom) of the stone. This is why cut quality matters more than raw carat weight when it comes to visual impact.
* Measurements refer to round brilliant cut diamonds with ideal proportions. Accuracy depends on your screen's pixel density — use the ruler to verify.
Notice that a 2.00ct diamond is twice the weight of a 1.00ct, but only about 26% larger in diameter (8.2mm vs 6.5mm). This is because weight increases cubically — much of the extra carat mass is distributed into the diamond's depth, not its visible face-up area. A 1 carat diamond already delivers excellent visual impact relative to its weight.
Pricing
What Does a 1.00ct Diamond Cost?
| Colour | Clarity | Cut | Diamantwerp | Typical Retail |
|---|---|---|---|---|
| D | VVS1 | Excellent | €8,500 | €25,000 |
| F | VS1 | Excellent | €5,200 | €15,000 |
| G | VS2 | Excellent | €4,000 | €12,000 |
| H | SI1 | Very Good | €2,800 | €8,000 |
| I | SI1 | Very Good | €1,600 | €5,000 |
The highlighted row (G / VS2 / Excellent) represents the sweet spot — it's the combination most of our customers choose. At this grade, any colour tint is invisible to the naked eye, inclusions can't be seen without 10× magnification, and the excellent cut ensures maximum sparkle. All at a price that's a fraction of what you'd pay elsewhere.
Prices are indicative and updated regularly. See our full diamond price guide →
Expert pick
Best Value: Our Recommendation
Our diamond experts have seen thousands of 1 carat stones come through Antwerp. Here's the combination that consistently delivers the best balance of beauty, sparkle, and value:
The Diamantwerp Sweet Spot
For a 1 carat diamond, we recommend prioritising cut quality above all else. The 1 carat mark is where the difference between an Excellent and Very Good cut becomes dramatically visible — an Excellent cut will maximise the diamond's fire and brilliance, making it appear larger and more impressive than a poorly cut stone of the same weight.
Prioritize Cut
An Excellent cut is non-negotiable at 1 carat. It maximises brilliance and can make the diamond appear 10–15% larger.
Save on Colour
At 1.00ct, G–H colour faces up white and bright. You'd need a side-by-side comparison with a D–E to notice any difference.
Eye-Clean Clarity
VS2 is the sweet spot — reliably eye-clean at 1 carat. SI1 can work too, but inspect each stone carefully at this size.
Shape Guide
Best Shapes for a 1 Carat Diamond
The shape of your diamond affects how large it appears face-up. Elongated shapes like oval, marquise, and pear have a larger surface area than round or princess cuts at the same carat weight — making them appear bigger for the same price.
For maximum visual impact at 1.00ct, consider an oval or pear shape. Their elongated profile covers more finger area while costing 15–20% less than an equivalent round. If classic brilliance is your priority, the round brilliant remains the gold standard for light performance.
Explore all shapes: Diamond Shapes Overview →
Expert Advice
Buying Tips for 1 Carat Diamonds
Consider a 0.90–0.99ct diamond. The 1 carat mark is the biggest price jump in the entire diamond market. A 0.95ct diamond looks virtually identical to a 1.00ct on the finger, but can cost 15–20% less. This "just-below" strategy is the single most effective way to save money on a diamond purchase.
Never compromise on cut. At 1 carat, the difference between an Excellent and Very Good cut is visible to the naked eye. A well-cut diamond appears larger, brighter, and more alive. Invest in the best cut grade you can afford — it has more impact on beauty than any other factor.
Choose your setting wisely. A solitaire setting lets a 1 carat diamond speak for itself — classic and timeless. A halo setting adds visual size, making your stone appear like a 1.30–1.50ct diamond. Both are excellent choices depending on your style preference.
Always insist on certification. Every diamond at Diamantwerp comes with an independent grading report from GIA, HRD Antwerp, or IGI. At the 1 carat price point, certification is essential — it protects your investment and guarantees you know exactly what you're paying for.
Consider fluorescence. A diamond with faint to medium blue fluorescence can appear slightly whiter in natural light, especially in lower colour grades (G–I). At 1 carat, this can save you €500–€1,000 without any visible downside. Our experts can help you identify stones where fluorescence is a positive trait.
Buy from the source. Antwerp handles over 80% of the world's rough diamond trade. By buying directly from Antwerp's diamond district — rather than through multiple middlemen — you skip the markups. Learn about our heritage →
Explore more
Other Carat Weights
Compare sizes and prices across our most popular carat weights
FAQ
Frequently Asked Questions
How much does a 1 carat diamond cost?
A 1 carat (1.00ct) diamond at Diamantwerp costs between €1,600 and €12,000, depending on the combination of cut quality, colour grade, and clarity. The most popular combination — G colour, VS2 clarity, Excellent cut — averages around €4,000. That's up to 70% less than you'd pay at a typical high-street jeweller for the same certified stone.
How big is a 1 carat diamond?
A well-cut 1.00 carat round brilliant diamond measures approximately 6.5mm in diameter. The exact dimensions vary depending on the diamond's shape and cut proportions. Elongated shapes like oval and pear can appear noticeably larger face-up at the same carat weight.
Is 1 carat a good size for an engagement ring?
A 1 carat diamond is the gold standard for engagement rings worldwide. It's the most sought-after weight, offering a perfect balance between impressive visual presence and value. In the US, the average engagement ring diamond is around 1.0–1.2 carats. With the right cut quality, a 1 carat stone delivers exceptional sparkle and a presence that's noticed and admired.
What is the best colour and clarity for a 1 carat diamond?
For a 1.00ct diamond, we recommend G–H colour and VS2–SI1 clarity. At this size, any slight colour tint is virtually invisible to the naked eye, and VS2 inclusions cannot be detected without 10× magnification. SI1 can also be eye-clean at 1 carat, but it's worth inspecting each stone individually. Prioritise cut quality — it has the greatest impact on sparkle.
Are Diamantwerp's 1 carat diamonds certified?
Yes. Every diamond we sell comes with an independent grading report from GIA, HRD Antwerp, or IGI — the world's three most respected diamond laboratories. Each certificate details the exact 4C grades, measurements, proportions, and any laser inscription. This gives you complete confidence in what you're purchasing.
