How much does a 2.00 to 2.99ct I SI1 natural cushion diamond cost?

As of October 2026, 2.00 to 2.99ct I SI1 natural cushion diamonds typically cost £5,108 GBP to £16,102 GBP, with a median price of £9,091 GBP. There are currently 336 diamonds matching this specification available across retailers.

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

About 33% of these diamonds are available at multiple retailers, with an average price spread of 49%. A comparison tool like Carat Hunter lets you see all the prices side by side.

2.00 to 2.99ct I SI1 Natural Cushion

Quick answer

As of October 2026, there are 336 natural cushion diamonds with I colour and SI1 clarity in the 2.00 to 2.99ct range available across retailers worldwide. Prices typically run £5,108 GBP to £16,102 GBP, with a median of £9,091 GBP. At least 56 retailers stock this exact specification, and 33% of the stones appear at more than one of them, with an average price spread of 49%. Half of all listings fall between £3,349 GBP and £5,457 GBP per carat. The same specification in lab grown form lists at a median of about £808 GBP per carat. Over the last 30 days the median price moved -1.2% and the number of listings moved +4.8%.

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. Cushion natural stones in the index: 2,948 USD per carat, +1.7% 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

336

Lowest Price

£2,722 GBP

Highest Price

£35,600 GBP

Average Price

£10,147 GBP