How much does a 1.50 to 1.99ct E SI1 natural marquise diamond cost?

As of October 2026, 1.50 to 1.99ct E SI1 natural marquise diamonds typically cost £6,880 GBP to £20,052 GBP, with a median price of £9,879 GBP. There are currently 60 diamonds matching this specification available across retailers.

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

About 31% of these diamonds are available at multiple retailers, with an average price spread of 33%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct E SI1 Natural Marquise

Quick answer

As of October 2026, there are 60 natural marquise diamonds with E colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run £6,880 GBP to £20,052 GBP, with a median of £9,879 GBP. At least 62 retailers stock this exact specification, and 31% of the stones appear at more than one of them, with an average price spread of 33%. Half of all listings fall between £5,334 GBP and £7,369 GBP per carat. The same specification in lab grown form lists at a median of about £312 GBP per carat. Over the last 30 days the median price moved -0.7% and the number of listings moved +13.2%.

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. Marquise natural stones in the index: 2,268 USD per carat, +10.8% 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

£4,612 GBP

Highest Price

£24,980 GBP

Average Price

£11,661 GBP