How much does a 1.00 to 1.49ct I SI2 natural cushion diamond cost?

As of November 2026, 1.00 to 1.49ct I SI2 natural cushion diamonds typically cost $2,080 NZD to $6,241 NZD, with a median price of $4,028 NZD. There are currently 359 diamonds matching this specification available across retailers.

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

About 36% of these diamonds are available at multiple retailers, with an average price spread of 59%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct I SI2 Natural Cushion

Quick answer

As of November 2026, there are 359 natural cushion diamonds with I colour and SI2 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run $2,080 NZD to $6,241 NZD, with a median of $4,028 NZD. At least 55 retailers stock this exact specification, and 36% of the stones appear at more than one of them, with an average price spread of 59%. Half of all listings fall between $2,777 NZD and $5,071 NZD per carat. Over the last 30 days the median price moved -1.3% and the number of listings moved +8.5%.

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. Cushion natural stones in the index: 2,881 USD per carat, -2.5% 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

359

Lowest Price

$1,353 NZD

Highest Price

$15,495 NZD

Average Price

$4,103 NZD

Market Intelligence

Retailers Selling

Cross Retailer %

36.0%

Price Spread

58.9%

30-Day Price Trend

-1.3%

30-Day Supply Change

+8.5%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$2,193/ct

10th Percentile

$1,214

Median

$2,193

90th Percentile

$3,629

Score Distribution

811 diamonds scored across 4 quality tiers

Excellent

83 (10.2%)

Very Good

173 (21.3%)

Good

249 (30.7%)

Average

306 (37.7%)

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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