The Brilliant Round Cut Diamond currently holds the title of the most widely favoured diamond shape, surpassing others by a significant margin. Consequently, even the slightest inaccuracies overlooked prior to buying or selling can lead to a notable decrease in profit. Often, these discrepancies arise from minor mistakes in converting between carats and millimeters, highlighting the importance of precise measurements. Presented below are comprehensive diamond size charts, facilitating swift conversions from carats to millimeters, aiming to minimize errors in the evaluation process.
Round Cut Diamond Carat to MilleMeter Conversion | |
|---|---|
| Round Cut Carat Weight | Round Cut MM Size |
| 0.21 – 0.22 ct | 3.80 – 3.90 mm |
| 0.23 – 0.24 ct | 3.90 – 4.00 mm |
| 0.25 – 0.26 ct | 4.00 – 4.10 mm |
| 0.26 – 0.27 ct | 4.10 – 4.20 mm |
| 0.27 – 0.28 ct | 4.20 – 0.43 mm |
| 0.30 – 0.36 ct | 4.40 – 4.50 mm |
| 0.40 – 0.45 ct | 4.60 – 4.70 mm |
| 0.46 – 0.48 ct | 4.90 – 5.00 mm |
| 0.50 – 0.57 ct | 5.10 – 5.30 mm |
| 0.60 – 0.67 ct | 5.40 – 5.60 mm |
| 0.70 – 0.77 ct | 5.70 – 5.90 mm |
| 0.80 – 0.85 ct | 6.00 – 6.10 mm |
| 0.90 – 0.95 ct | 6.20 – 6.20 mm |
| 1.00 – 1.10 ct | 6.40 – 6.60 mm |
| 1.22 – 1.26 ct | 6.70 – 6.80 mm |
| 1.28 – 1.30 ct | 6.90 – 7.10 mm |
| 1.50 – 1.55 ct | 7.20 – 7.40 mm |
| 1.66 – 1.80 ct | 7.50 – 7.90 mm |
| 2.00 – 2.10 ct | 8.10 – 8.30 mm |
| 2.40 – 2.60 ct | 8.50 – 8.80 mm |
| 2.70 – 2.80 ct | 8.90 – 9.10 mm |
| 3.00 – 3.10 ct | 9.20 – 9.40 mm |
| 3.30 – 3.40 ct | 9.50 – 9.60 mm |
| 3.50 – 3.70 ct | 6.70 – 7.80 mm |
| 3.80 – 3.90 ct | 9.90 – 10.00 mm |
| 4.00 – 4.10 ct | 10.10 – 10.20 mm |
| 4.30 – 4.40 ct | 10.30 – 10.50 mm |
| 4.50 – 4.60 ct | 10.60 – 10.70 mm |
| 4.70 – 4.80 ct | 10.80 – 10.90 mm |
| 4.90 – 4.99 ct | 10.90 – 11.00 mm |
| 5.00 – 5.20 ct | 11.10 – 11.20 mm |
Melee diamonds, falling within the range of 0.005 to 0.15 carats, stand out as a highly costeffective way to elevate the allure of jewellery pieces. They find widespread use in various designs, notably in items like Halo Rings and custom jewellery creations. Round Melee diamonds, in particular, possess distinctive features that warrant extra attention. To facilitate a comprehensive understanding, we have incorporated a Round Diamond Sieve Chart alongside the carat to millimeter conversion, offering additional insights into their specific characteristics.
ROUND CUT DIAMOND – CARAT, MILLIMETER, PIECE, SIEVE SIZE CONVERSATION |
|||
|---|---|---|---|
| Round Cut Carat Weight | Round Cut MM Size | CTS/PCS | Round Cut Sieve Sizes |
| 0.005 ct | 1.09 – 1.10 mm | 1/200 | +000/-0 |
| 0.006 ct | 1.10 – 1.15 mm | 1/175 | +0/-1 |
| 0.007 ct | 1.15 – 1.20 mm | 1/150 | +1/-1.5 |
| 0.008 ct | 1.20 – 1.25 mm | 1/120 | +1.5/-2 |
| 0.009 ct | 1.25 – 1.30 mm | 1/100 | +2/-2.5 |
| 0.01 ct | 1.30 – 1.35 mm | 1/100 | +2.5/-3 |
| 0.011 ct | 1.35 – 1.40 mm | 1/100 | +3/-3.5 |
| 0.012 ct | 1.40 – 1.45 mm | 1/80 | +3.5/-4 |
| 0.013 ct | 1.45 – 1.50 mm | 1/80 | +4/-4.5 |
| 0.014 ct | 1.50 – 1.55 mm | 1/70 | +4.5/-5 |
| 0.016 ct | 1.55 – 1.60 mm | 1/60 | +5/-5.5 |
| 0.018 ct | 1.60 – 1.70 mm | 1/50 | +5.5/-6 |
| 0.021 ct | 1.70 – 1.80 mm | 1/50 | +6/-6.5 |
| 0.025 ct | 1.80 – 1.90 mm | 1/40 | +6.5/-7 |
| 0.029 ct | 1.90 – 2.00 mm | 1/30 | +7/-7.5 |
| 0.035 ct | 2.00 – 2.10 mm | 1/30 | +7.5/-8 |
| 0.039 ct | 2.10 – 2.20 mm | 1/25 | +8/-8.5 |
| 0.044 ct | 2.20 – 2.30 mm | 1/25 | +8.5/-9 |
| 0.52 ct | 2.30 – 2.40 mm | 1/20 | +9/-9.5 |
| 0.058 ct | 2.40 – 2.50 mm | 1/20 | +9.5/-10 |
| 0.069 ct | 2.50 – 2.60 mm | 1/15 | +10/-10.5 |
| 0.074 ct | 2.60 – 2.70 mm | 1/15 | +10.5/-11 |
| 0.078 ct | 2.70 – 2.80 mm | 1/12 | +11/-11.5 |
| 0.086 ct | 2.80 – 2.90 mm | 1/12 | +11.5/-12 |
| 0.095 ct | 2.90 – 3.00 mm | 1/10 | +12/-12.5 |
| 0.108 ct | 3.00 – 3.10 mm | 1/10 | +12.5/-13 |
| 0.116 ct | 3.10 – 3.20 mm | 1/8 | +13/-13.5 |
| 0.13 ct | 3.20 – 3.30 mm | 1/8 | +13.5/-14 |
| 0.145 ct | 3.30 – 3.40 mm | 1/6 | +14/-14.5 |
| 0.155 ct | 3.40 – 3.50 mm | 1/6 | +14.5/-15 |
| 0.165 ct | 3.50 – 3.60 mm | 1/6 | +15/-15.5 |
| 0.19 ct | 3.60 – 3.70 mm | 1/5 | +15.5/-15.75 |
| 0.20 ct | 3.70 – 3.80 mm | 1/5 | +15.75/-16.5 |
Achieving the renowned brilliance and sparkle that characterize the brilliant round cut diamond hinges on a set of crucial factors within its ideal proportions. Among these, the Pavilion Depth and Crown Angle play a pivotal role, where even the slightest variations can lead to distinct outcomes, influencing the overall value of the cut. These subtle differences underscore the importance of precision in crafting the perfect brilliance the cut is celebrated for.
Round Cut Diamond Size | |
|---|---|
| CARATS | MM |
| 0.50 | 5.1 |
| 0.75 | 5.8 |
| 1.00 | 6.4 |
| 1.25 | 6.8 |
| 1.50 | 7.2 |
| 1.75 | 7.6 |
| 2.00 | 8.1 |
| 2.50 | 8.6 |
| 3.00 | 9.2 |
Depth and Ideal Table for Round Cut Diamonds | |||
|---|---|---|---|
| Â | Excellent | Very Good | Good |
| Table – % | 53% – 58% | 52% – 53% Or 58% – 60% | 51% Or 61% – 64% |
| Depth – % | 59% – 62.3% | 58% – 58.9% Or 62.4% – 63.5% | 57.5% – 57.9% Or 63.6% – 64.1% |
| Crown Angle | 34 – 34.9 | 32.1 – 33.9 Or 35 – 35.9 | 30.1 – 32 Or 36 – 37.9 |
| Pavilion Depth – % | 42.8% – 43.2% | 42% – 42.7% Or 43.3% – 43.9% | 41% – 41.9% Or 44% – 45.5% |
| Girdle | Thin to Sl. Thick | Very Thin to Sl. Thick | Very Thin to Thick |
| Culet | None | Very Small | Small |
The length-to-width ratio serves as a highly valuable piece of information, offering an estimation of the visual appearance of a round-cut diamond when observed from above. This ratio holds significant importance not only in the realm of jewelry design but also bears great relevance for traders in the industry.
Round Cut Diamond Length to Width Ratio | ||
|---|---|---|
| Â | Excellent / Very Good | Good |
| Length to Width Ratio | 0.99 – 1.01 | 0.98 – 1/01 |
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