How much does a 1.50 to 1.99ct I SI1 lab grown princess diamond cost?

As of October 2026, 1.50 to 1.99ct I SI1 lab grown princess diamonds typically cost $1,561 NZD to $8,989 NZD, with a median price of $3,217 NZD. There are currently 16 diamonds matching this specification available across retailers.

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

About 28% of these diamonds are available at multiple retailers, with an average price spread of 93%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct I SI1 Lab Grown Princess

Quick answer

As of October 2026, there are 16 lab grown princess diamonds with I colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run $1,561 NZD to $8,989 NZD, with a median of $3,217 NZD. At least 30 retailers stock this exact specification, and 28% of the stones appear at more than one of them, with an average price spread of 93%. Half of all listings fall between $695 NZD and $2,113 NZD per carat. The same specification in natural form lists at a median of about $6,640 NZD per carat. Over the last 30 days the median price moved +16.6% and the number of listings moved -17.7%.

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. Princess lab grown stones in the index: 461 USD per carat, -4.8% 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

Lowest Price

$951 NZD

Highest Price

$11,568 NZD

Average Price

$3,829 NZD

Market Intelligence

Retailers Selling

Cross Retailer %

28.3%

Price Spread

92.7%

30-Day Price Trend

+16.6%

30-Day Supply Change

-17.7%

Volatility (30d)

0.08

Price Range

Price per carat distribution across retailers

$862/ct

10th Percentile

$220

Median

$862

90th Percentile

$1,878

Score Distribution

24 diamonds scored across 4 quality tiers

Excellent

10 (41.7%)

Very Good

2 (8.3%)

Good

2 (8.3%)

Average

10 (41.7%)

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Related Specifications

D IF D VVS1 D VVS2 D VS1 D VS2 D SI1 E IF E VVS1 E VVS2 E VS1 E VS2 E SI1 F IF F VVS1 F VVS2 F VS1 F VS2 F SI1 G IF G VVS1 G VVS2 G VS1 G VS2 G SI1 H IF H VVS1 H VVS2 H VS1 H VS2 H SI1 I IF I VVS1 I VVS2 I VS1 I VS2 I SI1