How much does a 1.00 to 1.49ct J SI1 natural cushion diamond cost?

As of September 2026, 1.00 to 1.49ct J SI1 natural cushion diamonds typically cost £783 GBP to £2,410 GBP, with a median price of £1,344 GBP. There are currently 978 diamonds matching this specification available across retailers.

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

Compare prices across retailers on Carat Hunter to see all your options.

1.00 to 1.49ct J SI1 Natural Cushion

Quick answer

As of September 2026, there are 978 natural cushion diamonds with J colour and SI1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run £783 GBP to £2,410 GBP, with a median of £1,344 GBP. At least 48 retailers stock this exact specification. Half of all listings fall between £946 GBP and £1,662 GBP per carat. The same specification in lab grown form lists at a median of about £1,089 GBP per carat.

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

Caratlytics Diamond Price Index, August 2026: natural diamonds at 2,184 USD per carat and lab-grown at 464 USD per carat, a natural to lab ratio of 4.7 to 1. Cushion natural stones in the index: 2,792 USD per carat, +1.1% month on month. See the full index release

Figures come from live listings across more than 100 retailers and refresh daily. The index is a monthly release.

Last updated: September 2026

Available

978

Lowest Price

£519 GBP

Highest Price

£7,347 GBP

Average Price

£1,507 GBP

Market Intelligence

Retailers Selling

Price Spread

59.7%

Price Range

Price per carat distribution across retailers

$1,614/ct

10th Percentile

$1,055

Median

$1,614

90th Percentile

$2,834

Score Distribution

978 diamonds scored across 4 quality tiers

Excellent

91 (9.3%)

Very Good

234 (23.9%)

Good

288 (29.4%)

Average

365 (37.3%)

Find Your Diamond

Search 978 J SI1 cushion diamonds and compare prices.

Search Diamonds

Consider Instead

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

Lab-Grown J SI1Same specifications, lab-grown origin

Save 14%

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