How much does a 1.50 to 1.99ct I SI1 natural marquise diamond cost?

As of November 2026, 1.50 to 1.99ct I SI1 natural marquise diamonds typically cost HK$43,864 HKD to HK$139,324 HKD, with a median price of HK$69,106 HKD. There are currently 77 diamonds matching this specification available across retailers.

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

About 32% of these diamonds are available at multiple retailers, with an average price spread of 40%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct I SI1 Natural Marquise

Quick answer

As of November 2026, there are 77 natural marquise diamonds with I colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run HK$43,864 HKD to HK$139,324 HKD, with a median of HK$69,106 HKD. At least 58 retailers stock this exact specification, and 32% of the stones appear at more than one of them, with an average price spread of 40%. Half of all listings fall between HK$41,578 HKD and HK$62,029 HKD per carat. The same specification in lab grown form lists at a median of about HK$7,850 HKD per carat. Over the last 30 days the median price moved -4.3% and the number of listings moved +18.3%.

Three of the best scored stones at this specification right now:

Caratlytics Diamond Price Index, October 2026: natural diamonds at 2,202 USD per carat and lab-grown at 462 USD per carat, a natural to lab ratio of 4.8 to 1. Marquise natural stones in the index: 2,177 USD per carat, -4.2% 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: November 2026

Available

Lowest Price

HK$28,293 HKD

Highest Price

HK$221,155 HKD

Average Price

HK$81,612 HKD