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Round|Lab Grown|IGI

1.21ct F SI1 Round Lab Grown Diamond

VG • F/SI1 • IGI LG763668397

Shape and cutting style on the report: Round brilliant

Certificate IGI LG763668397

Diamond specifications and retailer prices

From £120 GBP
As of November 1, 2026
Save £575 GBP (83%) vs most expensive(unlock to see where)
13 retailers carry this diamond
Most expensive: £695 GBP at MOH London · As of November 1, 2026
View at MOH London

About this 1.21ct lab-grown round diamond

This 1.21ct lab-grown round 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 LG763668397 or 763668397. Listed at 13 retailers as of November 1, 2026, with prices from £120 to £695, a £575 spread on the same certified stone. MOH London lists it at £695. 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
SymmetryGood
FluorescenceNone
Crown angle36.1°
Pavilion angle39.7°
OriginLab Grown
Grading LabIGI
CertificateIGI LG763668397
Dimensions6.92 × 6.90 × 4.05 mm
L/W Ratio1.00
Girdle conditionFaceted
Culet sizePointed
Cert comments
As Grown - No indication of post-growth treatment This Laboratory Grown Diamond was created by High Pressure High Temperature (HPHT) growth process Type II
Top View
6.92 mm6.90 mm1.21 ctF / SI1
OriginLab Grown
CutVery Good
PolishVery Good
SymmetryGood
FluorescenceNone
CertificateIGI LG763668397
Side View
Table 60.0%Crown 36.1°Girdle: MED-STKPavilion 39.7°Culet: NoneDepth 58.7%

Caratlytics Score

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A
Excellent
Excellent quality and great value
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See the detailed 0 to 100 score with Quality, Value, Certification & Market breakdown

Price History

Last verified: Nov 1
Current: £695 GBP|Low: £114 GBP|High: £715 GBP|Avg: £307 GBP|-2.8%
MOH London
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Retailer 12
Retailer 13
November 6, 2026
Retailer 10£120 GBP
Retailer 11£134 GBP
Retailer 5£148 GBP
Retailer 4£149 GBP
Retailer 2£259 GBP
Retailer 8£259 GBP
Retailer 13£268 GBP
Retailer 3£276 GBP
Retailer 12£335 GBP
Retailer 6£336 GBP
Retailer 7£406 GBP
Retailer 9£411 GBP
MOH London£695 GBP

36 data points across 13 retailers

13 retailers£120 GBP to £695 GBP

A
Cheapest Retailer
-
£120 GBP
A
Retailer 2
-
£134 GBP
View
Final sale: no returns
Retailer 3
-
£148 GBP
View
Price last confirmed 52 days ago
Retailer 4
-
£149 GBP
View
Price last confirmed 12 days ago
B+
Retailer 5
-
£259 GBP
View
B+
Retailer 6
-
£259 GBP
View
B
Retailer 7
-
£268 GBP
View
B+
Retailer 8
-
£276 GBP
View
B+
Retailer 9
-
£335 GBP
View
B+
Retailer 10
-
£336 GBP
View
B
Retailer 11
-
£406 GBP
View
B
Retailer 12
-
£411 GBP
View
Most Expensive
B
MOH London
LG763668397 · Nov 1
£695 GBP
View
12 more retailers have this diamond
Prices start from £120 GBPSave up to £575 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
1.21ct Round
£120 GBP