How much does a 1.00 to 1.49ct I SI1 lab grown radiant diamond cost?

As of September 2026, 1.00 to 1.49ct I SI1 lab grown radiant diamonds typically cost $1,884 AUD to $4,784 AUD, with a median price of $2,005 AUD. There are currently 67 diamonds matching this specification available across retailers.

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

Compare prices across retailers on Carat Hunter to see all your options.

1.00 to 1.49ct I SI1 Lab Grown Radiant

Quick answer

As of September 2026, there are 67 lab grown radiant diamonds with I colour and SI1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run $1,884 AUD to $4,784 AUD, with a median of $2,005 AUD. At least 19 retailers stock this exact specification. Half of all listings fall between $1,106 AUD and $2,055 AUD per carat. The same specification in natural form lists at a median of about $4,223 AUD 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 lab grown stones in the index: 473 USD per carat, -12.5% 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

Lowest Price

$1,060 AUD

Highest Price

$6,960 AUD

Average Price

$2,559 AUD

Market Intelligence

Retailers Selling

Price Spread

51.4%

Price Range

Price per carat distribution across retailers

$1,326/ct

10th Percentile

$395

Median

$1,326

90th Percentile

$3,111

Score Distribution

67 diamonds scored across 3 quality tiers

Very Good

5 (7.5%)

Good

46 (68.7%)

Average

16 (23.9%)

Find Your Diamond

Search 67 I SI1 radiant diamonds and compare prices.

Search Diamonds

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