How much does a 1.00 to 1.49ct I SI1 natural marquise diamond cost?

As of November 2026, 1.00 to 1.49ct I SI1 natural marquise diamonds typically cost $2,491 SGD to $7,236 SGD, with a median price of $3,951 SGD. There are currently 250 diamonds matching this specification available across retailers.

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

About 39% of these diamonds are available at multiple retailers, with an average price spread of 46%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct I SI1 Natural Marquise

Quick answer

As of November 2026, there are 250 natural marquise diamonds with I colour and SI1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run $2,491 SGD to $7,236 SGD, with a median of $3,951 SGD. At least 62 retailers stock this exact specification, and 39% of the stones appear at more than one of them, with an average price spread of 46%. Half of all listings fall between $3,481 SGD and $5,439 SGD per carat. The same specification in lab grown form lists at a median of about $1,080 SGD per carat. Over the last 30 days the median price moved +0.5% and the number of listings moved +17.6%.

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

250

Lowest Price

$1,716 SGD

Highest Price

$15,594 SGD

Average Price

$4,619 SGD