How much does a 0.50 to 0.74ct D SI1 natural cushion diamond cost?

As of October 2026, 0.50 to 0.74ct D SI1 natural cushion diamonds typically cost £353 GBP to £1,198 GBP, with a median price of £600 GBP. There are currently 305 diamonds matching this specification available across retailers.

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

About 33% of these diamonds are available at multiple retailers, with an average price spread of 73%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.50 to 0.74ct D SI1 Natural Cushion

Quick answer

As of October 2026, there are 305 natural cushion diamonds with D colour and SI1 clarity in the 0.50 to 0.74ct range available across retailers worldwide. Prices typically run £353 GBP to £1,198 GBP, with a median of £600 GBP. At least 54 retailers stock this exact specification, and 33% of the stones appear at more than one of them, with an average price spread of 73%. Half of all listings fall between £807 GBP and £1,533 GBP per carat. The same specification in lab grown form lists at a median of about £414 GBP per carat. Over the last 30 days the median price moved -3.0% and the number of listings moved +4.9%.

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

305

Lowest Price

£243 GBP

Highest Price

£2,691 GBP

Average Price

£707 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

32.6%

Price Spread

72.5%

30-Day Price Trend

-3.0%

30-Day Supply Change

+4.9%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$1,330/ct

10th Percentile

$875

Median

$1,330

90th Percentile

$2,864

Score Distribution

863 diamonds scored across 4 quality tiers

Excellent

156 (18.1%)

Very Good

194 (22.5%)

Good

271 (31.4%)

Average

242 (28.0%)

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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