How much does a 5.00ct+ F SI2 lab grown cushion diamond cost?

As of October 2026, 5.00ct+ F SI2 lab grown cushion diamonds typically cost £445 GBP to £1,712 GBP, with a median price of £582 GBP. There are currently 3 diamonds matching this specification available across retailers.

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

About 57% of these diamonds are available at multiple retailers, with an average price spread of 116%. A comparison tool like Carat Hunter lets you see all the prices side by side.

5.00ct+ F SI2 Lab Grown Cushion

Quick answer

As of October 2026, there are 3 lab grown cushion diamonds with F colour and SI2 clarity in the 5.00ct+ range available across retailers worldwide. Prices typically run £445 GBP to £1,712 GBP, with a median of £582 GBP. At least 18 retailers stock this exact specification, and 57% of the stones appear at more than one of them, with an average price spread of 116%. Half of all listings fall between £128 GBP and £362 GBP per carat. The same specification in natural form lists at a median of about £11,571 GBP per carat. Over the last 30 days the median price moved -14.3% and the number of listings moved +25.8%.

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 lab grown stones in the index: 516 USD per carat, +6.9% 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

Lowest Price

£442 GBP

Highest Price

£4,446 GBP

Average Price

£937 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

57.1%

Price Spread

115.8%

30-Day Price Trend

-14.3%

30-Day Supply Change

+25.8%

Volatility (30d)

0.04

Price Range

Price per carat distribution across retailers

$268/ct

10th Percentile

$121

Median

$268

90th Percentile

$976

Score Distribution

5 diamonds scored across 3 quality tiers

Excellent

2 (40.0%)

Good

2 (40.0%)

Average

1 (20.0%)

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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