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

As of October 2026, 1.00 to 1.49ct I SI2 natural cushion diamonds typically cost $1,169 USD to $3,520 USD, with a median price of $2,278 USD. There are currently 375 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 October 2026, there are 375 natural cushion diamonds with I color and SI2 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run $1,169 USD to $3,520 USD, with a median of $2,278 USD. 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 $1,559 USD and $2,847 USD per carat. Over the last 30 days the median price moved -1.4% and the number of listings moved +10.7%.

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

375

Lowest Price

$759 USD

Highest Price

$8,715 USD

Average Price

$2,318 USD

Market Intelligence

Retailers Selling

Cross Retailer %

36.4%

Price Spread

58.7%

30-Day Price Trend

-1.4%

30-Day Supply Change

+10.7%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$2,194/ct

10th Percentile

$1,214

Median

$2,194

90th Percentile

$3,623

Score Distribution

901 diamonds scored across 4 quality tiers

Excellent

89 (9.9%)

Very Good

219 (24.3%)

Good

258 (28.6%)

Average

335 (37.2%)

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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