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

As of September 2026, 1.00 to 1.49ct I SI2 natural radiant diamonds typically cost $1,356 USD to $4,233 USD, with a median price of $2,326 USD. There are currently 515 diamonds matching this specification available across retailers.

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

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1.00 to 1.49ct I SI2 Natural Radiant

Quick answer

As of September 2026, there are 515 natural radiant diamonds with I color and SI2 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run $1,356 USD to $4,233 USD, with a median of $2,326 USD. At least 46 retailers stock this exact specification. Half of all listings fall between $1,698 USD and $2,741 USD per carat. The same specification in lab grown form lists at a median of about $1,708 USD per carat.

Three of the best scored stones at this specification right now:

Caratlytics Diamond Price Index, August 2026: natural diamonds at 2,184 USD per carat and lab-grown at 464 USD per carat, a natural to lab ratio of 4.7 to 1. Radiant natural stones in the index: 2,765 USD per carat, +6.0% month on month. See the full index release

Figures come from live listings across more than 100 retailers and refresh daily. The index is a monthly release.

Last updated: September 2026

Available

515

Lowest Price

$823 USD

Highest Price

$9,538 USD

Average Price

$2,544 USD

Market Intelligence

Retailers Selling

Price Spread

48.9%

Price Range

Price per carat distribution across retailers

$2,132/ct

10th Percentile

$1,444

Median

$2,132

90th Percentile

$3,369

Score Distribution

515 diamonds scored across 4 quality tiers

Excellent

44 (8.5%)

Very Good

142 (27.6%)

Good

138 (26.8%)

Average

191 (37.1%)

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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 21%

Lab-Grown I SI2Same specifications, lab-grown origin

Save 20%

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