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

As of October 2026, 1.50 to 1.99ct I SI1 lab grown oval diamonds typically cost $1,194 AUD to $3,530 AUD, with a median price of $1,422 AUD. There are currently 250 diamonds matching this specification available across retailers.

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

About 52% of these diamonds are available at multiple retailers, with an average price spread of 75%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct I SI1 Lab Grown Oval

Quick answer

As of October 2026, there are 250 lab grown oval diamonds with I colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run $1,194 AUD to $3,530 AUD, with a median of $1,422 AUD. At least 20 retailers stock this exact specification, and 52% of the stones appear at more than one of them, with an average price spread of 75%. Half of all listings fall between $1,337 AUD and $2,510 AUD per carat. The same specification in natural form lists at a median of about $6,839 AUD per carat. Over the last 30 days the median price moved -1.0% and the number of listings moved -0.5%.

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. Oval lab grown stones in the index: 453 USD per carat, -7.4% 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

250

Lowest Price

$1,166 AUD

Highest Price

$7,817 AUD

Average Price

$2,216 AUD

Market Intelligence

Retailers Selling

Cross Retailer %

52.4%

Price Spread

75.4%

30-Day Price Trend

-1.0%

30-Day Supply Change

-0.5%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$1,095/ct

10th Percentile

$861

Median

$1,095

90th Percentile

$1,878

Score Distribution

441 diamonds scored across 4 quality tiers

Excellent

232 (52.6%)

Very Good

16 (3.6%)

Good

17 (3.9%)

Average

176 (39.9%)

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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