How much does a 1.50 to 1.99ct G SI1 natural heart diamond cost?

As of October 2026, 1.50 to 1.99ct G SI1 natural heart diamonds typically cost £3,178 GBP to £9,729 GBP, with a median price of £5,787 GBP. There are currently 143 diamonds matching this specification available across retailers.

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

About 30% of these diamonds are available at multiple retailers, with an average price spread of 60%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct G SI1 Natural Heart

Quick answer

As of October 2026, there are 143 natural heart diamonds with G colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run £3,178 GBP to £9,729 GBP, with a median of £5,787 GBP. At least 59 retailers stock this exact specification, and 30% of the stones appear at more than one of them, with an average price spread of 60%. Half of all listings fall between £2,584 GBP and £4,570 GBP per carat. The same specification in lab grown form lists at a median of about £269 GBP per carat. Over the last 30 days the median price moved -1.8% and the number of listings moved +11.7%.

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 natural stones in the index: 2,374 USD per carat, +9.8% 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

143

Lowest Price

£1,433 GBP

Highest Price

£16,415 GBP

Average Price

£6,180 GBP