How much does a 5.00ct+ G SI2 natural cushion diamond cost?

As of October 2026, 5.00ct+ G SI2 natural cushion diamonds typically cost $79,027 AUD to $159,762 AUD, with a median price of $110,861 AUD. There are currently 17 diamonds matching this specification available across retailers.

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

About 30% of these diamonds are available at multiple retailers, with an average price spread of 33%. A comparison tool like Carat Hunter lets you see all the prices side by side.

5.00ct+ G SI2 Natural Cushion

Quick answer

As of October 2026, there are 17 natural cushion diamonds with G colour and SI2 clarity in the 5.00ct+ range available across retailers worldwide. Prices typically run $79,027 AUD to $159,762 AUD, with a median of $110,861 AUD. At least 28 retailers stock this exact specification, and 30% of the stones appear at more than one of them, with an average price spread of 33%. Half of all listings fall between $18,762 AUD and $25,993 AUD per carat. The same specification in lab grown form lists at a median of about $382 AUD per carat. Over the last 30 days the median price moved +0.3% and the number of listings moved -2.7%.

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

Lowest Price

$37,619 AUD

Highest Price

$436,667 AUD

Average Price

$120,319 AUD

Market Intelligence

Retailers Selling

Cross Retailer %

30.3%

Price Spread

33.0%

30-Day Price Trend

+0.3%

30-Day Supply Change

-2.7%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$15,410/ct

10th Percentile

$11,105

Median

$15,410

90th Percentile

$21,572

Score Distribution

43 diamonds scored across 4 quality tiers

Excellent

11 (25.6%)

Very Good

8 (18.6%)

Good

10 (23.3%)

Average

14 (32.6%)

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Consider Instead

Save money without compromising on what matters. These alternatives are visually similar but cost less.

Lab-Grown G SI2Same 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