How much does a 5.00ct+ G SI1 lab grown marquise diamond cost?

As of November 2026, 5.00ct+ G SI1 lab grown marquise diamonds typically cost $932 AUD to $3,797 AUD, with a median price of $1,552 AUD. There are currently 17 diamonds matching this specification available across retailers.

Where can I find the best price on a G SI1 marquise diamond?

About 44% of these diamonds are available at multiple retailers, with an average price spread of 107%. A comparison tool like Carat Hunter lets you see all the prices side by side.

5.00ct+ G SI1 Lab Grown Marquise

Quick answer

As of November 2026, there are 17 lab grown marquise diamonds with G colour and SI1 clarity in the 5.00ct+ range available across retailers worldwide. Prices typically run $932 AUD to $3,797 AUD, with a median of $1,552 AUD. At least 32 retailers stock this exact specification, and 44% of the stones appear at more than one of them, with an average price spread of 107%. Half of all listings fall between $300 AUD and $771 AUD per carat. The same specification in natural form lists at a median of about $27,873 AUD per carat. Over the last 30 days the median price moved -14.4% and the number of listings moved +39.8%.

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

Caratlytics Diamond Price Index, October 2026: natural diamonds at 2,202 USD per carat and lab-grown at 462 USD per carat, a natural to lab ratio of 4.8 to 1. Marquise lab grown stones in the index: 505 USD per carat, +1.6% 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

$800 AUD

Highest Price

$8,890 AUD

Average Price

$1,923 AUD

Market Intelligence

Retailers Selling

Cross Retailer %

44.4%

Price Spread

107.0%

30-Day Price Trend

-14.4%

30-Day Supply Change

+39.8%

Volatility (30d)

0.06

Price Range

Price per carat distribution across retailers

$308/ct

10th Percentile

$150

Median

$308

90th Percentile

$731

Score Distribution

25 diamonds scored across 4 quality tiers

Excellent

12 (48.0%)

Very Good

3 (12.0%)

Good

5 (20.0%)

Average

5 (20.0%)

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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