How much does a 0.20 to 0.49ct F SI1 lab grown radiant diamond cost?

As of October 2026, 0.20 to 0.49ct F SI1 lab grown radiant diamonds typically cost £85 GBP to £85 GBP, with a median price of £85 GBP. There are currently 1 diamonds matching this specification available across retailers.

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

About 100% of these diamonds are available at multiple retailers, with an average price spread of 61%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.20 to 0.49ct F SI1 Lab Grown Radiant

Quick answer

As of October 2026, there are 1 lab grown radiant diamonds with F colour and SI1 clarity in the 0.20 to 0.49ct range available across retailers worldwide. Prices typically run £85 GBP to £85 GBP, with a median of £85 GBP. At least 14 retailers stock this exact specification, and 100% of the stones appear at more than one of them, with an average price spread of 61%. Half of all listings fall between £358 GBP and £687 GBP per carat. The same specification in natural form lists at a median of about £1,123 GBP per carat.

Three of the best scored stones at this specification right now:

0.45ct Radiant F SI1, IGI, grade A, from £85 GBP

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. Radiant lab grown stones in the index: 474 USD per carat, -2.1% 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

£85 GBP

Highest Price

£382 GBP

Average Price

£85 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

100.0%

Price Spread

61.3%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$714/ct

10th Percentile

$302

Median

$714

90th Percentile

$1,116

Score Distribution

1 diamonds scored across 1 quality tiers

Excellent

1 (100.0%)

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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