How much does a 1.00 to 1.49ct I VS1 lab grown marquise diamond cost?

As of October 2026, 1.00 to 1.49ct I VS1 lab grown marquise diamonds typically cost £337 GBP to £1,714 GBP, with a median price of £440 GBP. There are currently 27 diamonds matching this specification available across retailers.

Where can I find the best price on a I VS1 marquise diamond?

About 23% of these diamonds are available at multiple retailers, with an average price spread of 112%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct I VS1 Lab Grown Marquise

Quick answer

As of October 2026, there are 27 lab grown marquise diamonds with I colour and VS1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run £337 GBP to £1,714 GBP, with a median of £440 GBP. At least 36 retailers stock this exact specification, and 23% of the stones appear at more than one of them, with an average price spread of 112%. Half of all listings fall between £354 GBP and £1,043 GBP per carat. The same specification in natural form lists at a median of about £3,856 GBP per carat. Over the last 30 days the median price moved +1.9% and the number of listings moved +6.9%.

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. Marquise lab grown stones in the index: 485 USD per carat, -3.2% 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

£113 GBP

Highest Price

£3,601 GBP

Average Price

£845 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

22.8%

Price Spread

111.9%

30-Day Price Trend

+1.9%

30-Day Supply Change

+6.9%

Volatility (30d)

0.01

Price Range

Price per carat distribution across retailers

$826/ct

10th Percentile

$287

Median

$826

90th Percentile

$2,606

Score Distribution

41 diamonds scored across 4 quality tiers

Excellent

13 (31.7%)

Very Good

12 (29.3%)

Good

2 (4.9%)

Average

14 (34.1%)

Find Your Diamond

Search 27 I VS1 marquise diamonds and compare prices.

Search Diamonds

Consider Instead

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

J VS1J colour is visually identical to I to the naked eye

Save 34%

I VS2VS2 inclusions are not visible without magnification

Save 7%

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