How much does a 0.75 to 0.99ct J SI1 natural radiant diamond cost?

As of October 2026, 0.75 to 0.99ct J SI1 natural radiant diamonds typically cost $1,590 NZD to $4,108 NZD, with a median price of $2,463 NZD. There are currently 64 diamonds matching this specification available across retailers.

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

About 31% of these diamonds are available at multiple retailers, with an average price spread of 64%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.75 to 0.99ct J SI1 Natural Radiant

Quick answer

As of October 2026, there are 64 natural radiant diamonds with J colour and SI1 clarity in the 0.75 to 0.99ct range available across retailers worldwide. Prices typically run $1,590 NZD to $4,108 NZD, with a median of $2,463 NZD. At least 51 retailers stock this exact specification, and 31% of the stones appear at more than one of them, with an average price spread of 64%. Half of all listings fall between $2,231 NZD and $4,038 NZD per carat. Over the last 30 days the median price moved -0.8% and the number of listings moved +17.9%.

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

$1,045 NZD

Highest Price

$7,525 NZD

Average Price

$2,690 NZD

Market Intelligence

Retailers Selling

Cross Retailer %

31.2%

Price Spread

64.0%

30-Day Price Trend

-0.8%

30-Day Supply Change

+17.9%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$1,591/ct

10th Percentile

$1,048

Median

$1,591

90th Percentile

$2,976

Score Distribution

216 diamonds scored across 4 quality tiers

Excellent

22 (10.2%)

Very Good

21 (9.7%)

Good

42 (19.4%)

Average

131 (60.6%)

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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