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Radiant|Lab Grown|IGI

1.21ct F SI1 Radiant Lab Grown Diamond

VG • F/SI1 • IGI LG640451130

Shape and cutting style on the report: Cut cornered rectangular modified brilliant

Certificate IGI LG640451130

Diamond specifications and retailer prices

From £341 GBP
As of November 5, 2026
1 retailer carries this diamond
Only listing: £341 GBP at Diamond Quarter
Only one retailer lists this diamond right now, and it is shown above, so there is nothing to unlock. Similar diamonds are carried by several retailers.
View at Diamond Quarter

About this 1.21ct lab-grown radiant diamond

This 1.21ct lab-grown radiant sits in the classic one-carat band, graded F colour (colourless) and SI1 clarity (slightly-included), with a very-good cut grade and certified by IGI LG640451130 or 640451130. Listed at a single retailer as of November 5, 2026. If it later appears at another store, Carat Hunter will surface the price comparison automatically. Cut grade matters more than carat or clarity for visible brilliance. If you can shift budget toward an Excellent or Ideal cut, do it before chasing higher colour or clarity.

The 4Cs

1.21
Carat
F
Colour
SI1
Clarity
Very Good
Cut

Specifications

CutVery Good
PolishVery Good
SymmetryExcellent
FluorescenceNone
Crown angle47.1°
Pavilion angle33.7°
OriginLab Grown
Grading LabIGI
CertificateIGI LG640451130
Dimensions7.62 × 5.11 × 3.48 mm
L/W Ratio1.49
Cert comments
This Laboratory Grown Diamond was created by Chemical Vapor Deposition (CVD) growth process Type IIa
Top View
7.62 mm5.11 mm1.21 ctF / SI1
OriginLab Grown
CutVery Good
PolishVery Good
SymmetryExcellent
FluorescenceNone
CertificateIGI LG640451130
Side View
Table 71.0%Crown 47.1°Girdle: STK-THKPavilion 33.7°CuletDepth 68.1%

Caratlytics Score

How it works →
B+
Very Good
Strong quality and value balance
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Price History

Last verified: Nov 5
Current: £341 GBP|Low: £341 GBP|High: £341 GBP|Avg: £341 GBP
September 26, 2026
Diamond Quarter£341 GBP

1 data point across 1 retailer

1 retailer

B+
Diamond Quarter
1.21SI1FLG30F403N · Nov 5
£341 GBP
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B+
1.21ct Radiant
£341 GBP