How much does a 0.75 to 0.99ct J SI1 natural princess diamond cost?

As of October 2026, 0.75 to 0.99ct J SI1 natural princess diamonds typically cost £534 GBP to £1,695 GBP, with a median price of £809 GBP. There are currently 130 diamonds matching this specification available across retailers.

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

About 35% of these diamonds are available at multiple retailers, with an average price spread of 66%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.75 to 0.99ct J SI1 Natural Princess

Quick answer

As of October 2026, there are 130 natural princess diamonds with J colour and SI1 clarity in the 0.75 to 0.99ct range available across retailers worldwide. Prices typically run £534 GBP to £1,695 GBP, with a median of £809 GBP. At least 54 retailers stock this exact specification, and 35% of the stones appear at more than one of them, with an average price spread of 66%. Half of all listings fall between £716 GBP and £1,311 GBP per carat. The same specification in lab grown form lists at a median of about £485 GBP per carat. Over the last 30 days the median price moved -4.4% and the number of listings moved +9.6%.

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. Princess natural stones in the index: 2,158 USD per carat, +5.7% 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

130

Lowest Price

£384 GBP

Highest Price

£2,860 GBP

Average Price

£949 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

34.8%

Price Spread

66.0%

30-Day Price Trend

-4.4%

30-Day Supply Change

+9.6%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$1,199/ct

10th Percentile

$828

Median

$1,199

90th Percentile

$2,561

Score Distribution

344 diamonds scored across 4 quality tiers

Excellent

39 (11.3%)

Very Good

51 (14.8%)

Good

91 (26.5%)

Average

163 (47.4%)

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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 46%

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