How much does a 1.50 to 1.99ct I SI2 lab grown heart diamond cost?

As of October 2026, 1.50 to 1.99ct I SI2 lab grown heart diamonds typically cost £531 GBP to £3,142 GBP, with a median price of £1,481 GBP. There are currently 4 diamonds matching this specification available across retailers.

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

About 19% of these diamonds are available at multiple retailers, with an average price spread of 91%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct I SI2 Lab Grown Heart

Quick answer

As of October 2026, there are 4 lab grown heart diamonds with I colour and SI2 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run £531 GBP to £3,142 GBP, with a median of £1,481 GBP. At least 10 retailers stock this exact specification, and 19% of the stones appear at more than one of them, with an average price spread of 91%. Half of all listings fall between £641 GBP and £1,770 GBP per carat. The same specification in natural form lists at a median of about £2,259 GBP per carat. Over the last 30 days the median price moved -17.8% and the number of listings moved +16.2%.

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

£316 GBP

Highest Price

£4,688 GBP

Average Price

£1,743 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

18.8%

Price Spread

90.8%

30-Day Price Trend

-17.8%

30-Day Supply Change

+16.2%

Volatility (30d)

0.04

Price Range

Price per carat distribution across retailers

$1,657/ct

10th Percentile

$809

Median

$1,657

90th Percentile

$2,489

Score Distribution

5 diamonds scored across 3 quality tiers

Very Good

2 (40.0%)

Good

1 (20.0%)

Average

2 (40.0%)

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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