How much does a 0.50 to 0.74ct I SI1 natural marquise diamond cost?

As of October 2026, 0.50 to 0.74ct I SI1 natural marquise diamonds typically cost $677 CAD to $1,850 CAD, with a median price of $1,023 CAD. There are currently 280 diamonds matching this specification available across retailers.

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

About 31% 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.

0.50 to 0.74ct I SI1 Natural Marquise

Quick answer

As of October 2026, there are 280 natural marquise diamonds with I color and SI1 clarity in the 0.50 to 0.74ct range available across retailers worldwide. Prices typically run $677 CAD to $1,850 CAD, with a median of $1,023 CAD. At least 61 retailers stock this exact specification, and 31% of the stones appear at more than one of them, with an average price spread of 41%. Half of all listings fall between $1,735 CAD and $2,596 CAD per carat. The same specification in lab grown form lists at a median of about $1,039 CAD per carat. Over the last 30 days the median price moved -1.3% 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. 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

280

Lowest Price

$417 CAD

Highest Price

$3,731 CAD

Average Price

$1,174 CAD