How much does a 0.75 to 0.99ct K SI1 natural oval diamond cost?

As of November 6, 2026, 0.75 to 0.99ct K SI1 natural oval diamonds typically cost £543 GBP to £1,649 GBP, with a median price of £865 GBP. There are currently 221 diamonds matching this specification available across retailers.

Where can I find the best price on a K SI1 oval diamond?

About 42% of these diamonds are available at multiple retailers, with an average price spread of 83%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.75 to 0.99ct K SI1 Natural Oval

Quick answer

As of November 6, 2026, there are 221 natural oval diamonds with K colour and SI1 clarity in the 0.75 to 0.99ct range available across retailers worldwide. Prices typically run £543 GBP to £1,649 GBP, with a median of £865 GBP. Half of all listings fall between £739 GBP and £1,561 GBP per carat. The same specification in lab grown form lists at a median of about £259 GBP per carat. Over the last 30 days the median price moved -3.4% and the number of listings moved +2.6%.

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. Oval natural stones in the index: 2,512 USD per carat, -7.2% 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

221

Lowest Price

£308 GBP

Highest Price

£3,265 GBP

Average Price

£1,012 GBP

Market Intelligence

Cross Retailer %

41.6%

Price Spread

83.2%

30-Day Price Trend

-3.4%

30-Day Supply Change

+2.6%

Volatility (30d)

0.02

Price Range

Price per carat distribution across retailers

$1,324/ct

10th Percentile

$814

Median

$1,324

90th Percentile

$2,452

Score Distribution

221 diamonds scored across 4 quality tiers

Excellent

36 (16.3%)

Very Good

52 (23.5%)

Good

47 (21.3%)

Average

86 (38.9%)

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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