How much does a 0.75 to 0.99ct D SI1 natural round diamond cost?

As of October 2026, 0.75 to 0.99ct D SI1 natural round diamonds typically cost £1,070 GBP to £3,529 GBP, with a median price of £1,859 GBP. There are currently 1,644 diamonds matching this specification available across retailers.

Where can I find the best price on a D SI1 round diamond?

About 32% of these diamonds are available at multiple retailers, with an average price spread of 62%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.75 to 0.99ct D SI1 Natural Round

Quick answer

As of October 2026, there are 1,644 natural round diamonds with D colour and SI1 clarity in the 0.75 to 0.99ct range available across retailers worldwide. Prices typically run £1,070 GBP to £3,529 GBP, with a median of £1,859 GBP. At least 68 retailers stock this exact specification, and 32% of the stones appear at more than one of them, with an average price spread of 62%. Half of all listings fall between £1,619 GBP and £2,885 GBP per carat. The same specification in lab grown form lists at a median of about £322 GBP per carat. Over the last 30 days the median price moved -1.9% and the number of listings moved +7.6%.

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

Caratlytics Diamond Price Index, September 2026: natural diamonds at 2,335 USD per carat and lab-grown at 443 USD per carat, a natural to lab ratio of 5.3 to 1. Round natural stones in the index: 2,248 USD per carat, +7.6% month on month. See the full index release

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

Last updated: October 2026

Available

1,644

Lowest Price

£645 GBP

Highest Price

£6,013 GBP

Average Price

£2,110 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

32.2%

Price Spread

61.9%

30-Day Price Trend

-1.9%

30-Day Supply Change

+7.6%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$2,718/ct

10th Percentile

$1,811

Median

$2,718

90th Percentile

$5,144

Score Distribution

3.4K diamonds scored across 4 quality tiers

Excellent

685 (20.2%)

Very Good

759 (22.3%)

Good

995 (29.3%)

Average

959 (28.2%)

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Consider Instead

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

D SI2SI2 inclusions are not visible without magnification

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Lab-Grown D SI1Same specifications, lab-grown origin

Save 84%

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