How much does a 3.00 to 4.99ct I I1 natural round diamond cost?

As of September 2026, 3.00 to 4.99ct I I1 natural round diamonds typically cost £8,928 GBP to £30,326 GBP, with a median price of £15,703 GBP. There are currently 127 diamonds matching this specification available across retailers.

Where can I find the best price on a I I1 round diamond?

About 48% of these diamonds are available at multiple retailers, with an average price spread of 76%. A comparison tool like Carat Hunter lets you see all the prices side by side.

3.00 to 4.99ct I I1 Natural Round

Quick answer

As of September 2026, there are 127 natural round diamonds with I colour and I1 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run £8,928 GBP to £30,326 GBP, with a median of £15,703 GBP. At least 23 retailers stock this exact specification, and 48% of the stones appear at more than one of them, with an average price spread of 76%. Half of all listings fall between £3,470 GBP and £7,611 GBP per carat. The same specification in lab grown form lists at a median of about £3,924 GBP per carat. Over the last 30 days the median price moved -11.2% and the number of listings moved -12.4%.

Three of the best scored stones at this specification right now:

Caratlytics Diamond Price Index, August 2026: natural diamonds at 2,184 USD per carat and lab-grown at 464 USD per carat, a natural to lab ratio of 4.7 to 1. Round natural stones in the index: 2,094 USD per carat, -3.8% month on month. See the full index release

Figures come from live listings across more than 100 retailers and refresh daily. The index is a monthly release.

Last updated: September 2026

Available

127

Lowest Price

£3,918 GBP

Highest Price

£61,805 GBP

Average Price

£18,136 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

47.5%

Price Spread

75.7%

30-Day Price Trend

-11.2%

30-Day Supply Change

-12.4%

Volatility (30d)

0.03

Price Range

Price per carat distribution across retailers

$7,374/ct

10th Percentile

$2,863

Median

$7,374

90th Percentile

$12,280

Score Distribution

127 diamonds scored across 4 quality tiers

Excellent

11 (8.7%)

Very Good

47 (37.0%)

Good

26 (20.5%)

Average

43 (33.9%)

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Consider Instead

Save money without compromising on what matters. These alternatives are visually similar but cost less.

Lab-Grown I I1Same specifications, lab-grown origin

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Related Specifications

D IF D VVS1 D VVS2 D VS1 D VS2 D SI1 E IF E VVS1 E VVS2 E VS1 E VS2 E SI1 F IF F VVS1 F VVS2 F VS1 F VS2 F SI1 G IF G VVS1 G VVS2 G VS1 G VS2 G SI1 H IF H VVS1 H VVS2 H VS1 H VS2 H SI1 I IF I VVS1 I VVS2 I VS1 I VS2 I SI1