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

As of October 2026, 1.00 to 1.49ct I SI2 natural radiant diamonds typically cost $1,895 SGD to $5,474 SGD, with a median price of $3,237 SGD. There are currently 168 diamonds matching this specification available across retailers.

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

About 33% of these diamonds are available at multiple retailers, with an average price spread of 56%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct I SI2 Natural Radiant

Quick answer

As of October 2026, there are 168 natural radiant diamonds with I colour and SI2 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run $1,895 SGD to $5,474 SGD, with a median of $3,237 SGD. At least 51 retailers stock this exact specification, and 33% of the stones appear at more than one of them, with an average price spread of 56%. Half of all listings fall between $2,169 SGD and $3,727 SGD per carat. Over the last 30 days the median price moved -0.6% and the number of listings moved +16.3%.

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

168

Lowest Price

$1,017 SGD

Highest Price

$8,727 SGD

Average Price

$3,461 SGD

Market Intelligence

Retailers Selling

Cross Retailer %

32.9%

Price Spread

56.1%

30-Day Price Trend

-0.6%

30-Day Supply Change

+16.3%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$2,166/ct

10th Percentile

$1,375

Median

$2,166

90th Percentile

$3,842

Score Distribution

539 diamonds scored across 4 quality tiers

Excellent

72 (13.4%)

Very Good

97 (18.0%)

Good

118 (21.9%)

Average

252 (46.8%)

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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