How much does a 3.00 to 4.99ct F SI1 natural cushion diamond cost?

As of October 2026, 3.00 to 4.99ct F SI1 natural cushion diamonds typically cost £21,353 GBP to £54,354 GBP, with a median price of £33,077 GBP. There are currently 113 diamonds matching this specification available across retailers.

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

About 40% of these diamonds are available at multiple retailers, with an average price spread of 30%. A comparison tool like Carat Hunter lets you see all the prices side by side.

3.00 to 4.99ct F SI1 Natural Cushion

Quick answer

As of October 2026, there are 113 natural cushion diamonds with F colour and SI1 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run £21,353 GBP to £54,354 GBP, with a median of £33,077 GBP. At least 53 retailers stock this exact specification, and 40% of the stones appear at more than one of them, with an average price spread of 30%. Half of all listings fall between £8,594 GBP and £11,621 GBP per carat. The same specification in lab grown form lists at a median of about £309 GBP per carat. Over the last 30 days the median price moved -0.6% and the number of listings moved +15.3%.

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

113

Lowest Price

£14,175 GBP

Highest Price

£98,122 GBP

Average Price

£36,264 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

40.4%

Price Spread

30.0%

30-Day Price Trend

-0.6%

30-Day Supply Change

+15.3%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$13,429/ct

10th Percentile

$9,585

Median

$13,429

90th Percentile

$18,206

Score Distribution

237 diamonds scored across 4 quality tiers

Excellent

39 (16.5%)

Very Good

68 (28.7%)

Good

48 (20.3%)

Average

82 (34.6%)

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Consider Instead

Save money without compromising on what matters. These alternatives are visually similar but cost less.

F SI2SI2 inclusions are not visible without magnification

Save 21%

Lab-Grown F SI1Same specifications, lab-grown origin

Save 97%

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