How much does a 1.50 to 1.99ct I SI1 lab grown heart diamond cost?

As of October 2026, 1.50 to 1.99ct I SI1 lab grown heart diamonds typically cost $261 AUD to $4,760 AUD, with a median price of $1,025 AUD. There are currently 2 diamonds matching this specification available across retailers.

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

About 55% of these diamonds are available at multiple retailers, with an average price spread of 158%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct I SI1 Lab Grown Heart

Quick answer

As of October 2026, there are 2 lab grown heart diamonds with I colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run $261 AUD to $4,760 AUD, with a median of $1,025 AUD. At least 22 retailers stock this exact specification, and 55% of the stones appear at more than one of them, with an average price spread of 158%. Half of all listings fall between $338 AUD and $1,486 AUD per carat. The same specification in natural form lists at a median of about $5,171 AUD per carat. Over the last 30 days the median price moved -22.2% and the number of listings moved +6.1%.

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. Heart lab grown stones in the index: 421 USD per carat, -1.8% 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

Lowest Price

$259 AUD

Highest Price

$11,232 AUD

Average Price

$2,015 AUD

Market Intelligence

Retailers Selling

Cross Retailer %

55.0%

Price Spread

158.2%

30-Day Price Trend

-22.2%

30-Day Supply Change

+6.1%

Volatility (30d)

0.04

Price Range

Price per carat distribution across retailers

$510/ct

10th Percentile

$138

Median

$510

90th Percentile

$2,009

Score Distribution

6 diamonds scored across 3 quality tiers

Very Good

4 (66.7%)

Good

1 (16.7%)

Average

1 (16.7%)

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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