How much does a 0.50 to 0.74ct K SI2 natural round diamond cost?

As of November 6, 2026, 0.50 to 0.74ct K SI2 natural round diamonds typically cost £261 GBP to £845 GBP, with a median price of £494 GBP. There are currently 1,945 diamonds matching this specification available across retailers.

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

About 38% of these diamonds are available at multiple retailers, with an average price spread of 63%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.50 to 0.74ct K SI2 Natural Round

Quick answer

As of November 6, 2026, there are 1,945 natural round diamonds with K colour and SI2 clarity in the 0.50 to 0.74ct range available across retailers worldwide. Prices typically run £261 GBP to £845 GBP, with a median of £494 GBP. Half of all listings fall between £624 GBP and £1,152 GBP per carat. The same specification in lab grown form lists at a median of about £428 GBP per carat. Over the last 30 days the median price moved -0.8% and the number of listings moved +2.3%.

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

Caratlytics Diamond Price Index, October 2026: natural diamonds at 2,202 USD per carat and lab-grown at 462 USD per carat, a natural to lab ratio of 4.8 to 1. Round natural stones in the index: 2,124 USD per carat, -6.9% month on month. See the full index release

Figures come from current listings across more than 125 retailers. The index is a monthly release.

Last updated: November 6, 2026

Available

1,945

Lowest Price

£105 GBP

Highest Price

£1,957 GBP

Average Price

£535 GBP

Market Intelligence

Cross Retailer %

38.0%

Price Spread

62.9%

30-Day Price Trend

-0.8%

30-Day Supply Change

+2.3%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$1,130/ct

10th Percentile

$629

Median

$1,130

90th Percentile

$1,827

Score Distribution

1.9K diamonds scored across 4 quality tiers

Excellent

350 (18.0%)

Very Good

501 (25.8%)

Good

289 (14.9%)

Average

805 (41.4%)

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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