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

As of September 2026, 3.00 to 4.99ct I SI1 natural round diamonds typically cost $35,119 NZD to $110,084 NZD, with a median price of $62,295 NZD. There are currently 1,316 diamonds matching this specification available across retailers.

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

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

3.00 to 4.99ct I SI1 Natural Round

Quick answer

As of September 2026, there are 1,316 natural round diamonds with I colour and SI1 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run $35,119 NZD to $110,084 NZD, with a median of $62,295 NZD. At least 56 retailers stock this exact specification. Half of all listings fall between $17,483 NZD and $23,907 NZD per carat. The same specification in lab grown form lists at a median of about $2,455 NZD 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

1,316

Lowest Price

$22,051 NZD

Highest Price

$220,186 NZD

Average Price

$69,287 NZD