How much does a 1.50 to 1.99ct J SI1 natural cushion diamond cost?

As of October 2026, 1.50 to 1.99ct J SI1 natural cushion diamonds typically cost $3,821 AUD to $10,193 AUD, with a median price of $6,138 AUD. There are currently 395 diamonds matching this specification available across retailers.

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

About 36% of these diamonds are available at multiple retailers, with an average price spread of 54%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct J SI1 Natural Cushion

Quick answer

As of October 2026, there are 395 natural cushion diamonds with J colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run $3,821 AUD to $10,193 AUD, with a median of $6,138 AUD. At least 56 retailers stock this exact specification, and 36% of the stones appear at more than one of them, with an average price spread of 54%. Half of all listings fall between $2,942 AUD and $5,037 AUD per carat. The same specification in lab grown form lists at a median of about $1,580 AUD per carat. Over the last 30 days the median price moved -0.0% and the number of listings moved +7.6%.

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. Cushion natural stones in the index: 2,948 USD per carat, +1.7% 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

395

Lowest Price

$2,510 AUD

Highest Price

$18,940 AUD

Average Price

$6,663 AUD

Market Intelligence

Retailers Selling

Cross Retailer %

36.1%

Price Spread

54.5%

30-Day Price Trend

-0.0%

30-Day Supply Change

+7.6%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$2,703/ct

10th Percentile

$1,682

Median

$2,703

90th Percentile

$4,458

Score Distribution

994 diamonds scored across 4 quality tiers

Excellent

152 (15.3%)

Very Good

182 (18.3%)

Good

236 (23.7%)

Average

424 (42.7%)

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Consider Instead

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

J SI2SI2 inclusions are not visible without magnification

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Lab-Grown J SI1Same specifications, lab-grown origin

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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