How much does a 0.50 to 0.74ct I SI2 natural round diamond cost?

As of October 2026, 0.50 to 0.74ct I SI2 natural round diamonds typically cost $446 USD to $1,442 USD, with a median price of $768 USD. There are currently 3,079 diamonds matching this specification available across retailers.

Where can I find the best price on a I SI2 round diamond?

About 34% of these diamonds are available at multiple retailers, with an average price spread of 60%. A comparison tool like Carat Hunter lets you see all the prices side by side.

0.50 to 0.74ct I SI2 Natural Round

Quick answer

As of October 2026, there are 3,079 natural round diamonds with I color and SI2 clarity in the 0.50 to 0.74ct range available across retailers worldwide. Prices typically run $446 USD to $1,442 USD, with a median of $768 USD. At least 60 retailers stock this exact specification, and 34% of the stones appear at more than one of them, with an average price spread of 60%. Half of all listings fall between $1,092 USD and $1,925 USD per carat. The same specification in lab grown form lists at a median of about $770 USD per carat. Over the last 30 days the median price moved -2.5% and the number of listings moved +8.2%.

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. 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

3,079

Lowest Price

$231 USD

Highest Price

$3,233 USD

Average Price

$866 USD