How much does a 1.50 to 1.99ct D SI2 natural round diamond cost?

As of October 2026, 1.50 to 1.99ct D SI2 natural round diamonds typically cost £3,738 GBP to £11,853 GBP, with a median price of £6,230 GBP. There are currently 695 diamonds matching this specification available across retailers.

Where can I find the best price on a D SI2 round diamond?

About 38% of these diamonds are available at multiple retailers, with an average price spread of 51%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct D SI2 Natural Round

Quick answer

As of October 2026, there are 695 natural round diamonds with D colour and SI2 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run £3,738 GBP to £11,853 GBP, with a median of £6,230 GBP. At least 58 retailers stock this exact specification, and 38% of the stones appear at more than one of them, with an average price spread of 51%. Half of all listings fall between £2,920 GBP and £4,838 GBP per carat. The same specification in lab grown form lists at a median of about £318 GBP per carat. Over the last 30 days the median price moved -1.2% and the number of listings moved +9.5%.

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

695

Lowest Price

£2,099 GBP

Highest Price

£22,641 GBP

Average Price

£7,088 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

37.6%

Price Spread

51.3%

30-Day Price Trend

-1.2%

30-Day Supply Change

+9.5%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$4,975/ct

10th Percentile

$3,010

Median

$4,975

90th Percentile

$8,134

Score Distribution

1.8K diamonds scored across 4 quality tiers

Excellent

459 (26.0%)

Very Good

374 (21.2%)

Good

341 (19.3%)

Average

594 (33.6%)

Find Your Diamond

Search 695 D SI2 round diamonds and compare prices.

Search Diamonds

Consider Instead

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

D I1I1 inclusions are not visible without magnification

Save 17%

Lab-Grown D SI2Same specifications, lab-grown origin

Save 91%

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