How much does a 5.00ct+ G SI1 natural radiant diamond cost?

As of October 2026, 5.00ct+ G SI1 natural radiant diamonds typically cost $122,702 AUD to $286,624 AUD, with a median price of $176,119 AUD. There are currently 17 diamonds matching this specification available across retailers.

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

About 34% of these diamonds are available at multiple retailers, with an average price spread of 36%. A comparison tool like Carat Hunter lets you see all the prices side by side.

5.00ct+ G SI1 Natural Radiant

Quick answer

As of October 2026, there are 17 natural radiant diamonds with G colour and SI1 clarity in the 5.00ct+ range available across retailers worldwide. Prices typically run $122,702 AUD to $286,624 AUD, with a median of $176,119 AUD. At least 12 retailers stock this exact specification, and 34% of the stones appear at more than one of them, with an average price spread of 36%. Half of all listings fall between $25,105 AUD and $36,517 AUD per carat. The same specification in lab grown form lists at a median of about $337 AUD per carat. Over the last 30 days the median price moved -2.3% and the number of listings moved +14.5%.

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. Radiant natural stones in the index: 3,091 USD per carat, +13.2% 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

$90,456 AUD

Highest Price

$422,344 AUD

Average Price

$191,175 AUD

Market Intelligence

Retailers Selling

Cross Retailer %

34.4%

Price Spread

35.6%

30-Day Price Trend

-2.3%

30-Day Supply Change

+14.5%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$22,488/ct

10th Percentile

$15,303

Median

$22,488

90th Percentile

$29,468

Score Distribution

47 diamonds scored across 4 quality tiers

Excellent

7 (14.9%)

Very Good

6 (12.8%)

Good

9 (19.1%)

Average

25 (53.2%)

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Consider Instead

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

Lab-Grown G SI1Same 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