How much does a 3.00 to 4.99ct J SI1 natural round diamond cost?

As of October 2026, 3.00 to 4.99ct J SI1 natural round diamonds typically cost £15,828 GBP to £38,852 GBP, with a median price of £24,683 GBP. There are currently 435 diamonds matching this specification available across retailers.

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

About 39% of these diamonds are available at multiple retailers, with an average price spread of 36%. A comparison tool like Carat Hunter lets you see all the prices side by side.

3.00 to 4.99ct J SI1 Natural Round

Quick answer

As of October 2026, there are 435 natural round diamonds with J colour and SI1 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run £15,828 GBP to £38,852 GBP, with a median of £24,683 GBP. At least 58 retailers stock this exact specification, and 39% of the stones appear at more than one of them, with an average price spread of 36%. Half of all listings fall between £5,346 GBP and £7,676 GBP per carat. The same specification in lab grown form lists at a median of about £5,033 GBP per carat. Over the last 30 days the median price moved -1.3% and the number of listings moved +11.0%.

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. Round natural stones in the index: 2,248 USD per carat, +7.6% 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

435

Lowest Price

£6,802 GBP

Highest Price

£77,156 GBP

Average Price

£26,211 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

38.6%

Price Spread

35.9%

30-Day Price Trend

-1.3%

30-Day Supply Change

+11.0%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$8,688/ct

10th Percentile

$5,974

Median

$8,688

90th Percentile

$11,968

Score Distribution

1.2K diamonds scored across 4 quality tiers

Excellent

105 (8.9%)

Very Good

299 (25.3%)

Good

216 (18.3%)

Average

560 (47.5%)

Find Your Diamond

Search 435 J SI1 round diamonds and compare prices.

Search Diamonds

Consider Instead

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

J SI2SI2 inclusions are not visible without magnification

Save 10%

Lab-Grown J SI1Same specifications, lab-grown origin

Save 77%

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