How much does a 0.20 to 0.49ct J SI2 natural radiant diamond cost?

As of October 2026, 0.20 to 0.49ct J SI2 natural radiant diamonds typically cost £230 GBP to £426 GBP, with a median price of £317 GBP. There are currently 7 diamonds matching this specification available across retailers.

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

About 12% of these diamonds are available at multiple retailers, with an average price spread of 42%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.20 to 0.49ct J SI2 Natural Radiant

Quick answer

As of October 2026, there are 7 natural radiant diamonds with J colour and SI2 clarity in the 0.20 to 0.49ct range available across retailers worldwide. Prices typically run £230 GBP to £426 GBP, with a median of £317 GBP. At least 22 retailers stock this exact specification, and 12% of the stones appear at more than one of them, with an average price spread of 42%. Half of all listings fall between £723 GBP and £1,070 GBP per carat. Over the last 30 days the median price moved -1.9% and the number of listings moved -2.7%.

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. Radiant natural stones in the index: 3,091 USD per carat, +13.2% 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

£119 GBP

Highest Price

£740 GBP

Average Price

£317 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

11.8%

Price Spread

42.5%

30-Day Price Trend

-1.9%

30-Day Supply Change

-2.7%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$1,089/ct

10th Percentile

$675

Median

$1,089

90th Percentile

$1,670

Score Distribution

44 diamonds scored across 4 quality tiers

Excellent

3 (6.8%)

Very Good

2 (4.5%)

Good

4 (9.1%)

Average

35 (79.5%)

Find Your Diamond

Search 7 J SI2 radiant diamonds and compare prices.

Search Diamonds

Consider Instead

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

J I1I1 inclusions are not visible without magnification

Save 6%

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