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

As of October 2026, 3.00 to 4.99ct I SI1 natural round diamonds typically cost HK$213,753 HKD to HK$552,056 HKD, with a median price of HK$331,548 HKD. There are currently 433 diamonds matching this specification available across retailers.

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

About 34% of these diamonds are available at multiple retailers, with an average price spread of 29%. A comparison tool like Carat Hunter lets you see all the prices side by side.

3.00 to 4.99ct I SI1 Natural Round

Quick answer

As of October 2026, there are 433 natural round diamonds with I colour and SI1 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run HK$213,753 HKD to HK$552,056 HKD, with a median of HK$331,548 HKD. At least 61 retailers stock this exact specification, and 34% of the stones appear at more than one of them, with an average price spread of 29%. Half of all listings fall between HK$80,239 HKD and HK$107,680 HKD per carat. The same specification in lab grown form lists at a median of about HK$3,730 HKD per carat. Over the last 30 days the median price moved -0.7% and the number of listings moved +5.7%.

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. Round natural stones in the index: 2,248 USD per carat, +7.6% 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

433

Lowest Price

HK$99,443 HKD

Highest Price

HK$996,792 HKD

Average Price

HK$357,164 HKD