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Round|Lab Grown|IGI

1.23ct I SI1 Round Lab Grown Diamond

ID • I/SI1 • IGI LG492123232

Shape and cutting style on the report: Round brilliant

Certificate IGI LG492123232

Diamond specifications and retailer prices

From £401 GBP
As of November 5, 2026
Save £3,040 GBP (88%) vs most expensive(unlock to see where)
13 retailers carry this diamond
Most expensive: £3,441 GBP at MOH London · As of November 5, 2026
View at MOH London

About this 1.23ct lab-grown round diamond

This 1.23ct lab-grown round sits in the classic one-carat band, graded I colour (near-colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG492123232 or 492123232. Listed at 13 retailers as of November 5, 2026, with prices from £401 to £3,441, a £3,040 spread on the same certified stone. MOH London lists it at £3,441. 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

1.23
Carat
I
Colour
SI1
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle33°
Pavilion angle41.1°
OriginLab Grown
Grading LabIGI
CertificateIGI LG492123232
Dimensions6.96 × 6.93 × 4.20 mm
L/W Ratio1.00
Girdle conditionFaceted
Culet sizePointed
Cert comments
This Laboratory Grown Diamond was created by Chemical Vapor Deposition (CVD) growth process and may include post-growth treatment Type IIa
Top View
6.96 mm6.93 mm1.23 ctI / SI1
OriginLab Grown
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG492123232
Side View
Table 58.5%Crown 33°Girdle: MediumPavilion 41.1°Culet: NoneDepth 60.5%

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: Nov 5
Current: £3,441 GBP|Low: £401 GBP|High: £3,496 GBP|Avg: £1,587 GBP|-0.2%
MOH London
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
November 5, 2026
Retailer 6£401 GBP
Retailer 5£1,042 GBP
Retailer 11£1,133 GBP
Retailer 10£1,166 GBP
Retailer 7£1,208 GBP
Retailer 9£1,208 GBP
Retailer 2£1,571 GBP
Retailer 8£1,907 GBP
Retailer 4£2,051 GBP
Retailer 3£2,265 GBP
MOH London£3,441 GBP

41 data points across 11 retailers

13 retailers£401 GBP to £3,441 GBP

A
Cheapest Retailer
-
£401 GBP
B+
Retailer 2
-
£1,042 GBP
View
B+
Retailer 3
-
£1,133 GBP
View
B+
Retailer 4
-
£1,166 GBP
View
Final sale: no returns
B+
Retailer 5
-
£1,208 GBP
View
Retailer 6
-
£1,208 GBP
View
Price last confirmed 25 days ago
B
Retailer 7
-
£1,334 GBP
View
B+
Retailer 8
-
£1,571 GBP
View
B
Retailer 9
-
£1,907 GBP
View
B
Retailer 10
-
£2,051 GBP
View
B
Retailer 11
-
£2,193 GBP
View
B
Retailer 12
-
£2,265 GBP
View
Most Expensive
B
MOH London
LG492123232 · Nov 5
£3,441 GBP
View
12 more retailers have this diamond
Prices start from £401 GBPSave up to £3,040 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
1.23ct Round
£401 GBP