How much does a 5.00ct+ I SI2 natural oval diamond cost?

As of September 2026, 5.00ct+ I SI2 natural oval diamonds typically cost £23,993 GBP to £88,583 GBP, with a median price of £46,925 GBP. There are currently 134 diamonds matching this specification available across retailers.

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

Compare prices across retailers on Carat Hunter to see all your options.

5.00ct+ I SI2 Natural Oval

Quick answer

As of September 2026, there are 134 natural oval diamonds with I colour and SI2 clarity in the 5.00ct+ range available across retailers worldwide. Prices typically run £23,993 GBP to £88,583 GBP, with a median of £46,925 GBP. At least 9 retailers stock this exact specification. Half of all listings fall between £17,041 GBP and £22,395 GBP per carat. The same specification in lab grown form lists at a median of about £11,393 GBP per carat.

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. Oval natural stones in the index: 2,380 USD per carat, -9.6% 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

134

Lowest Price

£13,183 GBP

Highest Price

£278,290 GBP

Average Price

£50,971 GBP