How much does a 1.50 to 1.99ct K SI1 natural radiant diamond cost?

As of November 6, 2026, 1.50 to 1.99ct K SI1 natural radiant diamonds typically cost €2,344 EUR to €6,087 EUR, with a median price of €3,565 EUR. There are currently 169 diamonds matching this specification available across retailers.

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

About 41% of these diamonds are available at multiple retailers, with an average price spread of 49%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.50 to 1.99ct K SI1 Natural Radiant

Quick answer

As of November 6, 2026, there are 169 natural radiant diamonds with K colour and SI1 clarity in the 1.50 to 1.99ct range available across retailers worldwide. Prices typically run €2,344 EUR to €6,087 EUR, with a median of €3,565 EUR. Half of all listings fall between €1,806 EUR and €2,920 EUR per carat. The same specification in lab grown form lists at a median of about €1,377 EUR per carat. Over the last 30 days the median price moved -1.7% and the number of listings moved +20.7%.

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. Radiant natural stones in the index: 3,108 USD per carat, +0.3% month on month. See the full index release

Figures come from current listings across more than 125 retailers. The index is a monthly release.

Last updated: November 6, 2026

Available

169

Lowest Price

€1,777 EUR

Highest Price

€12,916 EUR

Average Price

€3,938 EUR

Market Intelligence

Cross Retailer %

41.4%

Price Spread

49.1%

30-Day Price Trend

-1.7%

30-Day Supply Change

+20.7%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$2,535/ct

10th Percentile

$1,730

Median

$2,535

90th Percentile

$4,040

Score Distribution

169 diamonds scored across 4 quality tiers

Excellent

36 (21.3%)

Very Good

38 (22.5%)

Good

38 (22.5%)

Average

57 (33.7%)

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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