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Round|Natural|IGI

0.51ct I SI2 Round Natural Diamond

EX • I/SI2 • IGI 670417121

Shape and cutting style on the report: Round brilliant

Certificate IGI 670417121

Diamond specifications and retailer prices

From £192 GBP
As of November 6, 2026
Save £832 GBP (81%) vs most expensive(unlock to see where)
12 retailers carry this diamond
Most expensive: £1,025 GBP at NZ Jewellers · As of November 4, 2026
View at NZ Jewellers

About this 0.51ct natural round diamond

This 0.51ct natural round sits in the half to three-quarter carat band, graded I colour (near-colourless) and SI2 clarity (slightly-included), with a top-tier cut grade and certified by IGI 670417121. Listed at 12 retailers as of November 4, 2026, with prices from £192 to £1,025, a £832 spread on the same certified stone. NZ Jewellers lists it at £1,025. 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

0.51
Carat
I
Colour
SI2
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle35.6°
Pavilion angle41°
OriginNatural
Grading LabIGI
CertificateIGI 670417121
Dimensions5.10 × 5.05 × 3.18 mm
L/W Ratio1.01
Girdle conditionFaceted
Culet sizePointed
Top View
5.10 mm5.05 mm0.51 ctI / SI2
OriginNatural
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI 670417121
Side View
Table 57.0%Crown 35.6°Girdle: MED-STKPavilion 41°Culet: NoneDepth 62.7%

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 6
Current: £192 GBP|Low: £192 GBP|High: £624 GBP|Avg: £354 GBP|-1.9%
Retailer 1
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
November 6, 2026
Retailer 1£192 GBP
Retailer 5£246 GBP
Retailer 3£275 GBP
Retailer 6£289 GBP
Retailer 7£377 GBP
Retailer 2£435 GBP
Retailer 4£617 GBP

44 data points across 7 retailers

12 retailers£192 GBP to £1,025 GBP

A
Cheapest Retailer
-
£192 GBP
A
Retailer 2
-
£246 GBP
View
Final sale: no returns
A
Retailer 3
-
£267 GBP
View
A
Retailer 4
-
£275 GBP
View
Retailer 5
-
£288 GBP
View
Price last confirmed 8 days ago
A
Retailer 6
-
£298 GBP
View
A
Retailer 7
-
£360 GBP
View
A
Retailer 8
-
£364 GBP
View
A
Retailer 9
-
£377 GBP
View
A
Retailer 10
-
£435 GBP
View
B+
Retailer 11
-
£617 GBP
View
Most Expensive
B
NZ Jewellers
027d91a0-08be-4dfe-9965-8ccb7e7514a0 · Nov 4
£1,025 GBP
$1,379 USD
View
11 more retailers have this diamond
Prices start from £192 GBPSave up to £832 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
0.51ct Round
£192 GBP