How much does a 3.00 to 4.99ct I SI1 natural asscher diamond cost?

As of October 2026, 3.00 to 4.99ct I SI1 natural asscher diamonds typically cost £16,449 GBP to £41,197 GBP, with a median price of £23,387 GBP. There are currently 23 diamonds matching this specification available across retailers.

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

About 50% of these diamonds are available at multiple retailers, with an average price spread of 41%. A comparison tool like Carat Hunter lets you see all the prices side by side.

3.00 to 4.99ct I SI1 Natural Asscher

Quick answer

As of October 2026, there are 23 natural asscher diamonds with I colour and SI1 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run £16,449 GBP to £41,197 GBP, with a median of £23,387 GBP. At least 46 retailers stock this exact specification, and 50% of the stones appear at more than one of them, with an average price spread of 41%. Half of all listings fall between £6,078 GBP and £9,237 GBP per carat. The same specification in lab grown form lists at a median of about £1,639 GBP per carat. Over the last 30 days the median price moved -3.7% and the number of listings moved +15.5%.

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. Asscher natural stones in the index: 2,504 USD per carat, -3.3% 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

£14,322 GBP

Highest Price

£73,049 GBP

Average Price

£25,858 GBP