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Round|Lab Grown|IGI

8.31ct G SI1 Round Lab Grown Diamond

ID • G/SI1 • IGI LG595371329

Shape and cutting style on the report: Round brilliant

Certificate IGI LG595371329

Diamond specifications and retailer prices

From £861 GBP
$1,153 USD
As of October 29, 2026
Save £3,188 GBP (79%) vs most expensive(unlock to see where)
15 retailers carry this diamond
Most expensive: £4,048 GBP at Blue Nile · As of October 31, 2026
View at Blue Nile

About this 8.31ct lab-grown round diamond

This 8.31ct lab-grown round sits in the over five carat band, graded G colour (near-colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG595371329 or 595371329. Listed at 15 retailers as of October 29, 2026, with prices from £861 to £4,048, a £3,188 spread on the same certified stone. Blue Nile lists it at £4,048. SI-grade stones are eye-clean roughly 60 to 70% of the time at this carat range. Check the inclusion plot on the cert and ask the retailer for high-resolution video before buying.

The 4Cs

8.31
Carat
G
Colour
SI1
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle35.5°
Pavilion angle40.6°
OriginLab Grown
Grading LabIGI
CertificateIGI LG595371329
Dimensions13.00 × 12.92 × 7.98 mm
L/W Ratio1.01
Girdle conditionFaceted
Culet sizePointed
Top View
13.00 mm12.92 mm8.31 ctG / SI1
OriginLab Grown
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG595371329
Side View
Table 57.0%Crown 35.5°Girdle: MED-STKPavilion 40.6°Culet: NoneDepth 61.5%

Caratlytics Score

How it works →
A
Excellent
Excellent quality and great value
Unlock full score analysis
See the detailed 0 to 100 score with Quality, Value, Certification & Market breakdown

Price History

Last verified: Oct 29
Current: £4,048 GBP|Low: £751 GBP|High: £4,048 GBP|Avg: £1,701 GBP
Blue Nile
Retailer 2
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Retailer 5
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Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Retailer 12
Retailer 13
Retailer 14
Retailer 15
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Retailer 17
November 1, 2026
Retailer 8£841 GBP
Retailer 4£861 GBP
Retailer 9£871 GBP
Retailer 12£937 GBP
Retailer 17£999 GBP
Retailer 16£1,015 GBP
Retailer 11£1,127 GBP
Retailer 6£1,400 GBP
Retailer 10£1,423 GBP
Retailer 2£1,442 GBP
Retailer 5£1,585 GBP
Retailer 3£1,871 GBP
Retailer 13£1,967 GBP
Retailer 15£3,225 GBP
Retailer 14£3,561 GBP
Retailer 7£4,030 GBP
Blue Nile£4,048 GBP

41 data points across 17 retailers

15 retailers£861 GBP to £4,048 GBP

A
Cheapest Retailer
-
£861 GBP
$1,153 USD
A
Retailer 2
-
£937 GBP
$1,255 USD
View
A
Retailer 3
-
£999 GBP
$1,338 USD
View
Retailer 4
-
£1,015 GBP
View
Price last confirmed 15 days ago
A
Retailer 5
-
£1,127 GBP
$1,510 USD
View
B+
Retailer 6
-
£1,400 GBP
$1,876 USD
View
B+
Retailer 7
-
£1,423 GBP
€1,816 EUR
View
B+
Retailer 8
-
£1,442 GBP
View
B+
Retailer 9
-
£1,585 GBP
$2,124 USD
View
B+
Retailer 10
-
£1,871 GBP
$2,507 USD
View
B+
Retailer 11
-
£1,967 GBP
$2,636 USD
View
B
Retailer 12
-
£3,225 GBP
View
B
Retailer 13
-
£3,561 GBP
$4,771 USD
View
B
Retailer 14
-
£4,030 GBP
$5,400 USD
View
Most Expensive
B
Blue Nile
25246920 · Oct 31
£4,048 GBP
$5,424 USD
View
14 more retailers have this diamond
Prices start from £861 GBPSave up to £3,188 GBP

Carat Hunter is not affiliated with, endorsed by, or sponsored by any retailer listed. Retailer information is from publicly available sources and may not be current. Verify details directly with the retailer before purchasing. Return terms as we hold them. Check the retailer's own returns page before you buy.

A
8.31ct Round
£861 GBP