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Round|Lab Grown|IGI

1.21ct H SI1 Round Lab Grown Diamond

ID • H/SI1 • IGI LG817652948

Shape and cutting style on the report: Round brilliant

Certificate IGI LG817652948

Diamond specifications and retailer prices

From £169 GBP
As of November 4, 2026
Save £232 GBP (58%) vs most expensive(unlock to see where)
16 retailers carry this diamond
Most expensive: £774 GBP at Reve Diamonds · As of October 25, 2026
View at Reve Diamonds

About this 1.21ct lab-grown round diamond

This 1.21ct lab-grown round sits in the classic one-carat band, graded H colour (near-colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG817652948 or 817652948. Listed at 16 retailers as of November 4, 2026, with a 137% 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

1.21
Carat
H
Colour
SI1
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishVery Good
SymmetryVery Good
FluorescenceNone
Crown angle34.9°
Pavilion angle40.5°
OriginLab Grown
Grading LabIGI
CertificateIGI LG817652948
Dimensions6.86 × 6.82 × 4.14 mm
L/W Ratio1.01
Girdle conditionFaceted
Culet sizeNone
Cert comments
This Laboratory Grown Diamond was created by Chemical Vapor Deposition (CVD) growth process Type IIa
Top View
6.86 mm6.82 mm1.21 ctH / SI1
OriginLab Grown
CutIdeal
PolishVery Good
SymmetryVery Good
FluorescenceNone
CertificateIGI LG817652948
Side View
Table 60.0%Crown 34.9°Girdle: MED-STKPavilion 40.5°Culet: NoneDepth 60.5%

Caratlytics Score

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A
Excellent
Excellent quality and great value
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Price History

Last verified: Nov 4
Current: £220 GBP|Low: £112 GBP|High: £1,058 GBP|Avg: £405 GBP|-22.1%
Retailer 1
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Reve Diamonds
November 6, 2026
Retailer 10£112 GBP
Retailer 9£169 GBP
Retailer 4£194 GBP
Retailer 1£220 GBP
Retailer 7£287 GBP
Retailer 6£295 GBP
Retailer 5£305 GBP
Retailer 2£383 GBP
Retailer 8£401 GBP
Retailer 11£444 GBP
Retailer 3£659 GBP
Reve Diamonds£774 GBP

34 data points across 12 retailers

16 retailers£169 GBP to £401 GBP

Retailer 1
-
£136 GBP
Price last confirmed 27 days ago
Retailer 2
-
£158 GBP
View
Price last confirmed 28 days ago
Retailer 3
-
£169 GBP
View
Price last confirmed 27 days ago
B+
Retailer 4
-
£169 GBP
View
A
Retailer 5
-
£194 GBP
View
A
Retailer 6
-
£220 GBP
View
A
Retailer 7
-
£287 GBP
View
A
Retailer 8
-
£295 GBP
View
A
Retailer 9
-
£305 GBP
View
Retailer 10
-
£334 GBP
View
Price last confirmed 11 days ago
Retailer 11
-
£383 GBP
View
Price last confirmed 11 days ago
A
Retailer 12
-
£401 GBP
View
Retailer 13
-
£444 GBP
View
Price last confirmed 10 days ago
Retailer 14
-
£543 GBP
View
Price last confirmed 28 days ago
Retailer 15
-
£659 GBP
View
Price last confirmed 16 days ago
Most Expensive
Reve Diamonds
CA45F42F7 · Oct 25
£774 GBP
$1,041 USD
View
Price last confirmed 12 days ago
15 more retailers have this diamond
Prices start from £169 GBPSave up to £232 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
£169 GBP