How much does a 3.00 to 4.99ct I SI2 lab grown marquise diamond cost?

As of September 2026, 3.00 to 4.99ct I SI2 lab grown marquise diamonds typically cost $17,222 SGD to $57,651 SGD, with a median price of $41,814 SGD. There are currently 8 diamonds matching this specification available across retailers.

Where can I find the best price on a I SI2 marquise diamond?

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

3.00 to 4.99ct I SI2 Lab Grown Marquise

Quick answer

As of September 2026, there are 8 lab grown marquise diamonds with I colour and SI2 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run $17,222 SGD to $57,651 SGD, with a median of $41,814 SGD. At least 4 retailers stock this exact specification. Half of all listings fall between $7,293 SGD and $15,461 SGD per carat. The same specification in natural form lists at a median of about $12,136 SGD per carat.

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

4.01ct Marquise I SI2, AGS, score 70 of 100, from $78,153 SGD

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. Marquise lab grown stones in the index: 500 USD per carat, -14.7% 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

Lowest Price

$13,622 SGD

Highest Price

$80,765 SGD

Average Price

$39,568 SGD

Market Intelligence

Retailers Selling

Price Spread

92.8%

Price Range

Price per carat distribution across retailers

$6,938/ct

10th Percentile

$3,848

Median

$6,938

90th Percentile

$13,721

Score Distribution

8 diamonds scored across 3 quality tiers

Very Good

1 (12.5%)

Good

1 (12.5%)

Average

6 (75.0%)

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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