How much does a 1.00 to 1.49ct G SI1 natural round diamond cost?

As of September 2026, 1.00 to 1.49ct G SI1 natural round diamonds typically cost £1,611 GBP to £3,857 GBP, with a median price of £2,296 GBP. There are currently 7,473 diamonds matching this specification available across retailers.

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

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

1.00 to 1.49ct G SI1 Natural Round

Quick answer

As of September 2026, there are 7,473 natural round diamonds with G colour and SI1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run £1,611 GBP to £3,857 GBP, with a median of £2,296 GBP. At least 65 retailers stock this exact specification. Half of all listings fall between £2,038 GBP and £2,811 GBP per carat. The same specification in lab grown form lists at a median of about £556 GBP 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. Round natural stones in the index: 2,094 USD per carat, -3.8% 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

7,473

Lowest Price

£485 GBP

Highest Price

£13,616 GBP

Average Price

£2,550 GBP