Round|Natural|GIA

4.21ct K SI1 Round Natural Diamond

EX • K/SI1 • GIA 2231859024

Certificate GIA 2231859024

Diamond specifications and retailer prices

From £22,181 GBP
As of November 4, 2026
Save £7,751 GBP (26%) vs most expensive(unlock to see where)
21 retailers carry this diamond
Most expensive: £43,520 GBP at MOH London · As of October 21, 2026
View at MOH London

About this 4.21ct natural round diamond

This 4.21ct natural round sits in the three to five carat band, graded K colour (faint-tinted) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by GIA 2231859024. Listed at 21 retailers as of November 4, 2026, with a 35% 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

4.21
Carat
K
Colour
SI1
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceFaint
Crown angle35.5°
Pavilion angle41°
OriginNatural
Grading LabGIA
CertificateGIA 2231859024
Dimensions10.31 × 10.24 × 6.42 mm
L/W Ratio1.01
Top View
10.31 mm10.24 mm4.21 ctK / SI1
OriginNatural
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceFaint
CertificateGIA 2231859024
Side View
Table 58.0%Crown 35.5°Girdle: Med. - Sli. ThickPavilion 41°Culet: NoneDepth 62.5%

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 4
Current: £43,520 GBP|Low: £21,417 GBP|High: £43,809 GBP|Avg: £28,373 GBP|-0.4%
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
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Retailer 16
Retailer 17
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Retailer 19
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Retailer 22
November 6, 2026
Retailer 15£21,417 GBP
Retailer 19£22,181 GBP
Retailer 20£22,530 GBP
Retailer 13£23,146 GBP
Retailer 22£23,440 GBP
Retailer 21£23,890 GBP
Retailer 7£24,307 GBP
Retailer 17£24,704 GBP
Retailer 11£25,234 GBP
Retailer 14£26,896 GBP
Retailer 2£27,375 GBP
Retailer 4£27,717 GBP
Retailer 3£28,839 GBP
Retailer 6£28,872 GBP
Retailer 9£28,872 GBP
Retailer 12£29,639 GBP
Retailer 16£29,932 GBP
Retailer 10£30,026 GBP
Retailer 8£31,182 GBP
Retailer 5£34,061 GBP
Retailer 18£34,873 GBP
MOH London£43,520 GBP

25 data points across 22 retailers

21 retailers£22,181 GBP to £29,932 GBP

A
Cheapest Retailer
-
£22,181 GBP
A
Retailer 2
-
£22,530 GBP
View
A
Retailer 3
-
£23,146 GBP
View
A
Retailer 4
-
£23,440 GBP
View
A
Retailer 5
-
£23,890 GBP
View
Retailer 6
-
£24,307 GBP
View
Price last confirmed 16 days ago
A
Retailer 7
-
£24,704 GBP
View
Retailer 8
-
£25,234 GBP
View
Price last confirmed 14 days ago
Retailer 9
-
£26,896 GBP
View
Price last confirmed 13 days ago
B+
Retailer 10
-
£27,375 GBP
View
Retailer 11
-
£27,717 GBP
View
Price last confirmed 13 days ago
Retailer 12
-
£28,872 GBP
View
Price last confirmed 14 days ago
Retailer 13
-
£28,872 GBP
View
Price last confirmed 15 days ago
Retailer 14
-
£29,639 GBP
View
Price last confirmed 23 days ago
B+
Retailer 15
-
£29,932 GBP
View
Retailer 16
-
£30,026 GBP
View
Price last confirmed 15 days ago
Retailer 17
-
£31,182 GBP
View
Price last confirmed 14 days ago
Retailer 18
-
£33,435 GBP
View
Price last confirmed 13 days ago
Retailer 19
-
£34,061 GBP
View
Price last confirmed 15 days ago
Retailer 20
-
£34,873 GBP
View
Price last confirmed 9 days ago
Most Expensive
MOH London
620BE549C · Oct 21
£43,520 GBP
View
Price last confirmed 16 days ago
20 more retailers have this diamond
Prices start from £22,181 GBPSave up to £7,751 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
4.21ct Round
£22,181 GBP