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Round|Lab Grown|IGI

1.28ct F SI1 Round Lab Grown Diamond

EX • F/SI1 • IGI LG788620074

Shape and cutting style on the report: Round brilliant

Certificate IGI LG788620074

Diamond specifications and retailer prices

From £128 GBP
As of November 5, 2026
Save £613 GBP (83%) vs most expensive(unlock to see where)
15 retailers carry this diamond
Most expensive: £741 GBP at MOH London · As of November 2, 2026
View at MOH London

About this 1.28ct lab-grown round diamond

This 1.28ct 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 LG788620074 or 788620074. Listed at 15 retailers as of November 2, 2026, with prices from £128 to £741, a £613 spread on the same certified stone. MOH London lists it at £741. 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

1.28
Carat
F
Colour
SI1
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle33°
Pavilion angle40.6°
OriginLab Grown
Grading LabIGI
CertificateIGI LG788620074
Dimensions7.06 × 7.03 × 4.18 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
7.06 mm7.03 mm1.28 ctF / SI1
OriginLab Grown
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG788620074
Side View
Table 61.0%Crown 33°Girdle: MED-STKPavilion 40.6°Culet: NoneDepth 59.3%

Caratlytics Score

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A
Excellent
Excellent quality and great value
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Price History

Last verified: Nov 5
Current: £741 GBP|Low: £128 GBP|High: £750 GBP|Avg: £368 GBP
MOH London
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
November 6, 2026
Retailer 7£128 GBP
Retailer 8£158 GBP
Retailer 2£272 GBP
Retailer 4£279 GBP
Retailer 9£283 GBP
Retailer 5£344 GBP
Retailer 10£347 GBP
Retailer 6£403 GBP
Retailer 3£471 GBP
MOH London£741 GBP

43 data points across 10 retailers

15 retailers£128 GBP to £741 GBP

A
Cheapest Retailer
-
£128 GBP
A
Retailer 2
-
£148 GBP
View
A
Retailer 3
-
£158 GBP
View
Retailer 4
-
£158 GBP
View
Price last confirmed 12 days ago
A
Retailer 5
-
£272 GBP
View
A
Retailer 6
-
£279 GBP
View
B+
Retailer 7
-
£283 GBP
View
A
Retailer 8
-
£306 GBP
View
A
Retailer 9
-
£344 GBP
View
B+
Retailer 10
-
£347 GBP
View
B+
Retailer 11
-
£403 GBP
View
B+
Retailer 12
-
£471 GBP
View
B
Retailer 13
-
£510 GBP
View
B+
Retailer 14
-
£550 GBP
View
Most Expensive
B
MOH London
LG788620074 · Nov 2
£741 GBP
View
14 more retailers have this diamond
Prices start from £128 GBPSave up to £613 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
1.28ct Round
£128 GBP