How much does a 0.75 to 0.99ct I SI2 natural radiant diamond cost?

As of October 2026, 0.75 to 0.99ct I SI2 natural radiant diamonds typically cost $1,679 NZD to $3,874 NZD, with a median price of $2,585 NZD. There are currently 47 diamonds matching this specification available across retailers.

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

About 22% of these diamonds are available at multiple retailers, with an average price spread of 52%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.75 to 0.99ct I SI2 Natural Radiant

Quick answer

As of October 2026, there are 47 natural radiant diamonds with I colour and SI2 clarity in the 0.75 to 0.99ct range available across retailers worldwide. Prices typically run $1,679 NZD to $3,874 NZD, with a median of $2,585 NZD. At least 46 retailers stock this exact specification, and 22% of the stones appear at more than one of them, with an average price spread of 52%. Half of all listings fall between $2,326 NZD and $3,846 NZD per carat. The same specification in lab grown form lists at a median of about $742 NZD per carat. Over the last 30 days the median price moved +1.2% and the number of listings moved +8.7%.

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. 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

$1,044 NZD

Highest Price

$9,129 NZD

Average Price

$2,706 NZD

Market Intelligence

Retailers Selling

Cross Retailer %

22.4%

Price Spread

51.7%

30-Day Price Trend

+1.2%

30-Day Supply Change

+8.7%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$1,658/ct

10th Percentile

$1,069

Median

$1,658

90th Percentile

$2,968

Score Distribution

164 diamonds scored across 4 quality tiers

Excellent

11 (6.7%)

Very Good

25 (15.2%)

Good

21 (12.8%)

Average

107 (65.2%)

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Consider Instead

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

J SI2J colour is visually identical to I to the naked eye

Save 12%

Lab-Grown I SI2Same specifications, lab-grown origin

Save 75%

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