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Round|Lab Grown|IGI

1.51ct D SI1 Round Lab Grown Diamond

EX • D/SI1 • IGI LG731538751

Shape and cutting style on the report: Round brilliant

Certificate IGI LG731538751

Diamond specifications and retailer prices

From £156 GBP
As of November 5, 2026
Save £755 GBP (83%) vs most expensive(unlock to see where)
20 retailers carry this diamond
Most expensive: £1,174 GBP at Brilliant Earth · As of October 18, 2026
View at Brilliant Earth

About this 1.51ct lab-grown round diamond

This 1.51ct lab-grown round sits in the one-and-a-half to two carat band, graded D colour (colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG731538751 or 731538751. Listed at 20 retailers as of November 5, 2026, with a 484% 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

1.51
Carat
D
Colour
SI1
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle36°
Pavilion angle40.8°
OriginLab Grown
Grading LabIGI
CertificateIGI LG731538751
Dimensions7.31 × 7.27 × 4.58 mm
L/W Ratio1.01
Girdle conditionFaceted
Culet sizePointed
Top View
7.31 mm7.27 mm1.51 ctD / SI1
OriginLab Grown
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG731538751
Side View
Table 56.0%Crown 36°Girdle: THN-MEDPavilion 40.8°Culet: NoneDepth 62.8%

Caratlytics Score

How it works →
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 5
Current: £1,174 GBP|Low: £150 GBP|High: £1,174 GBP|Avg: £428 GBP
Brilliant Earth
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
November 6, 2026
Retailer 10£156 GBP
Retailer 3£194 GBP
Retailer 11£262 GBP
Retailer 2£300 GBP
Retailer 7£321 GBP
Retailer 4£354 GBP
Retailer 9£429 GBP
Retailer 8£473 GBP
Retailer 6£565 GBP
Retailer 5£774 GBP
Brilliant Earth£1,174 GBP

41 data points across 11 retailers

20 retailers£156 GBP to £911 GBP

A
Cheapest Retailer
-
£156 GBP
A
Retailer 2
-
£175 GBP
View
Final sale: no returns
A
Retailer 3
-
£181 GBP
View
Retailer 4
-
£194 GBP
View
Price last confirmed 12 days ago
A
Retailer 5
-
£194 GBP
View
B+
Retailer 6
-
£262 GBP
View
A
Retailer 7
-
£300 GBP
View
A
Retailer 8
-
£321 GBP
View
A
Retailer 9
-
£329 GBP
View
A
Retailer 10
-
£354 GBP
View
B+
Retailer 11
-
£383 GBP
View
B+
Retailer 12
-
£429 GBP
View
B+
Retailer 13
-
£473 GBP
View
B
Retailer 14
-
£565 GBP
View
B
Retailer 15
-
£623 GBP
View
Retailer 16
-
£626 GBP
View
Price last confirmed 9 days ago
B
Retailer 17
-
£662 GBP
View
B
Retailer 18
-
£774 GBP
View
B
Retailer 19
-
£911 GBP
View
Most Expensive
Brilliant Earth
16956960A · Oct 18
£1,174 GBP
$1,580 USD
View
Price last confirmed 18 days ago
19 more retailers have this diamond
Prices start from £156 GBPSave up to £755 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
1.51ct Round
£156 GBP