How much does a 1.50 to 1.99ct J SI2 natural round diamond cost?

As of October 2026, 1.50 to 1.99ct J SI2 natural round diamonds typically cost $3,523 AUD to $11,795 AUD, with a median price of $6,614 AUD. There are currently 1,446 diamonds matching this specification available across retailers.

Where can I find the best price on a J SI2 round diamond?

About 45% of these diamonds are available at multiple retailers, with an average price spread of 55%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct J SI2 Natural Round

Quick answer

As of October 2026, there are 1,446 natural round diamonds with J colour and SI2 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run $3,523 AUD to $11,795 AUD, with a median of $6,614 AUD. At least 57 retailers stock this exact specification, and 45% of the stones appear at more than one of them, with an average price spread of 55%. Half of all listings fall between $3,044 AUD and $5,281 AUD per carat. The same specification in lab grown form lists at a median of about $1,698 AUD per carat. Over the last 30 days the median price moved -1.9% and the number of listings moved +18.6%.

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. Round natural stones in the index: 2,248 USD per carat, +7.6% 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

1,446

Lowest Price

$1,776 AUD

Highest Price

$23,672 AUD

Average Price

$7,186 AUD

Market Intelligence

Retailers Selling

Cross Retailer %

45.4%

Price Spread

54.8%

30-Day Price Trend

-1.9%

30-Day Supply Change

+18.6%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$2,872/ct

10th Percentile

$1,647

Median

$2,872

90th Percentile

$4,670

Score Distribution

3.5K diamonds scored across 4 quality tiers

Excellent

656 (19.0%)

Very Good

966 (27.9%)

Good

690 (20.0%)

Average

1,146 (33.1%)

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Consider Instead

Save money without compromising on what matters. These alternatives are visually similar but cost less.

J I1I1 inclusions are not visible without magnification

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Lab-Grown J SI2Same specifications, lab-grown origin

Save 58%

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