How much does a 1.00 to 1.49ct I I1 natural marquise diamond cost?

As of November 2026, 1.00 to 1.49ct I I1 natural marquise diamonds typically cost £1,085 GBP to £5,490 GBP, with a median price of £2,680 GBP. There are currently 39 diamonds matching this specification available across retailers.

Where can I find the best price on a I I1 marquise diamond?

About 19% of these diamonds are available at multiple retailers, with an average price spread of 75%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct I I1 Natural Marquise

Quick answer

As of November 2026, there are 39 natural marquise diamonds with I colour and I1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run £1,085 GBP to £5,490 GBP, with a median of £2,680 GBP. At least 27 retailers stock this exact specification, and 19% of the stones appear at more than one of them, with an average price spread of 75%. Half of all listings fall between £1,277 GBP and £2,657 GBP per carat. Over the last 30 days the median price moved -2.3% and the number of listings moved +5.0%.

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. Marquise natural stones in the index: 2,268 USD per carat, +10.8% 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: November 2026

Available

Lowest Price

£569 GBP

Highest Price

£7,569 GBP

Average Price

£2,963 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

19.0%

Price Spread

74.7%

30-Day Price Trend

-2.3%

30-Day Supply Change

+5.0%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$2,473/ct

10th Percentile

$1,276

Median

$2,473

90th Percentile

$4,351

Score Distribution

153 diamonds scored across 4 quality tiers

Excellent

5 (3.3%)

Very Good

27 (17.6%)

Good

13 (8.5%)

Average

108 (70.6%)

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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