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

As of October 2026, 1.00 to 1.49ct D SI1 natural cushion diamonds typically cost £1,270 GBP to £4,463 GBP, with a median price of £2,183 GBP. There are currently 297 diamonds matching this specification available across retailers.

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

About 32% of these diamonds are available at multiple retailers, with an average price spread of 64%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct D SI1 Natural Cushion

Quick answer

As of October 2026, there are 297 natural cushion diamonds with D colour and SI1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run £1,270 GBP to £4,463 GBP, with a median of £2,183 GBP. At least 60 retailers stock this exact specification, and 32% of the stones appear at more than one of them, with an average price spread of 64%. Half of all listings fall between £1,465 GBP and £2,738 GBP per carat. The same specification in lab grown form lists at a median of about £338 GBP per carat. Over the last 30 days the median price moved -2.2% and the number of listings moved +7.8%.

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

297

Lowest Price

£927 GBP

Highest Price

£7,562 GBP

Average Price

£2,522 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

31.8%

Price Spread

63.9%

30-Day Price Trend

-2.2%

30-Day Supply Change

+7.8%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$2,670/ct

10th Percentile

$1,635

Median

$2,670

90th Percentile

$4,710

Score Distribution

779 diamonds scored across 4 quality tiers

Excellent

130 (16.7%)

Very Good

148 (19.0%)

Good

212 (27.2%)

Average

289 (37.1%)

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Consider Instead

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

D SI2SI2 inclusions are not visible without magnification

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Lab-Grown D SI1Same specifications, lab-grown origin

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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