Round|Lab Grown|IGI

1.31ct F SI1 Round Lab Grown Diamond

ID • F/SI1 • IGI LG771657198

Shape and cutting style on the report: Round brilliant

Certificate IGI LG771657198

Diamond specifications and retailer prices

From £135 GBP
As of October 30, 2026
Save £311 GBP (70%) vs most expensive(unlock to see where)
17 retailers carry this diamond
Most expensive: £785 GBP at Reve Diamonds · As of October 25, 2026
View at Reve Diamonds

About this 1.31ct lab-grown round diamond

This 1.31ct lab-grown round sits in the one-and-a-quarter to one-and-a-half carat band, graded F colour (colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG771657198 or 771657198. Listed at 17 retailers as of October 30, 2026, with a 230% spread between the cheapest and most expensive listing. That is exactly the kind of price-discovery gap Carat Hunter was built to surface. 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

1.31
Carat
F
Colour
SI1
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle33.3°
Pavilion angle41.2°
OriginLab Grown
Grading LabIGI
CertificateIGI LG771657198
Dimensions7.05 × 7.02 × 4.33 mm
L/W Ratio1.00
Girdle conditionFaceted
Culet sizePointed
Cert comments
This Laboratory Grown Diamond was created by Chemical Vapor Deposition (CVD) growth process Type IIa
Top View
7.05 mm7.02 mm1.31 ctF / SI1
OriginLab Grown
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG771657198
Side View
Table 58.0%Crown 33.3°Girdle: MED-STKPavilion 41.2°Culet: NoneDepth 61.6%

Caratlytics Score

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A
Excellent
Excellent quality and great value
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Price History

Last verified: Oct 30
Current: £247 GBP|Low: £114 GBP|High: £864 GBP|Avg: £359 GBP|-18.2%
Retailer 1
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Retailer 12
Retailer 13
Retailer 14
Retailer 15
Retailer 16
Retailer 17
Reve Diamonds
November 6, 2026
Retailer 6£117 GBP
Retailer 7£130 GBP
Retailer 15£135 GBP
Retailer 5£145 GBP
Retailer 9£195 GBP
Retailer 1£247 GBP
Retailer 16£252 GBP
Retailer 17£254 GBP
Retailer 14£319 GBP
Retailer 12£368 GBP
Retailer 13£385 GBP
Retailer 11£386 GBP
Retailer 4£389 GBP
Retailer 10£446 GBP
Retailer 3£465 GBP
Retailer 8£505 GBP
Retailer 2£676 GBP
Reve Diamonds£785 GBP

39 data points across 18 retailers

17 retailers£135 GBP to £446 GBP

Retailer 1
-
£117 GBP
Price last confirmed 11 days ago
A
Retailer 2
-
£135 GBP
View
Retailer 3
-
£145 GBP
View
Price last confirmed 10 days ago
B+
Retailer 4
-
£195 GBP
View
A
Retailer 5
-
£247 GBP
View
Retailer 6
-
£252 GBP
View
Price last confirmed 9 days ago
A
Retailer 7
-
£319 GBP
View
Retailer 8
-
£360 GBP
View
Price last confirmed 16 days ago
A
Retailer 9
-
£368 GBP
View
B+
Retailer 10
-
£385 GBP
View
B+
Retailer 11
-
£386 GBP
View
Retailer 12
-
£389 GBP
View
Price last confirmed 11 days ago
B+
Retailer 13
-
£446 GBP
View
Retailer 14
-
£465 GBP
View
Price last confirmed 13 days ago
Retailer 15
-
£505 GBP
View
Price last confirmed 10 days ago
Retailer 16
-
£676 GBP
View
Price last confirmed 11 days ago
Most Expensive
Reve Diamonds
1E17ECC5F · Oct 25
£785 GBP
$1,056 USD
View
Price last confirmed 12 days ago
16 more retailers have this diamond
Prices start from £135 GBPSave up to £311 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
1.31ct Round
£135 GBP