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Marquise|Natural|GIA

2.51ct I SI2 Marquise Natural Diamond

EX • I/SI2

Diamond specifications and retailer prices

From £14,901 GBP
$19,996 USD
As of November 2, 2026
Save £5,234 GBP (26%) vs most expensive(unlock to see where)
11 retailers carry this diamond
Most expensive: £23,966 GBP at NZ Jewellers · As of October 24, 2026
View at NZ Jewellers

About this 2.51ct natural marquise diamond

This 2.51ct natural marquise sits in the two to three carat band, graded I colour (near-colourless) and SI2 clarity (slightly-included), with a top-tier cut grade stated by the retailer rather than the lab and certified by GIA. Listed at 11 retailers as of November 2, 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

2.51
Carat
I
Colour
SI2
Clarity
Excellent
Cut (retailer stated)

Specifications

Cut (retailer stated)Excellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
OriginNatural
Grading LabGIA
Dimensions12.40 × 6.80 × 4.60 mm
L/W Ratio1.82
Top View
12.40 mm6.80 mm2.51 ctI / SI2
OriginNatural
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateGIA
Side View
Table 58.0%CrownGirdle: Slightly ThickPavilionCulet: NoneDepth 67.8%

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 2
Current: £23,966 GBP|Low: £14,901 GBP|High: £23,966 GBP|Avg: £18,512 GBP
NZ Jewellers
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
October 26, 2026
Retailer 3£14,901 GBP
Retailer 5£16,237 GBP
Retailer 8£16,917 GBP
Retailer 11£17,627 GBP
Retailer 4£17,763 GBP
Retailer 10£18,327 GBP
Retailer 9£18,746 GBP
Retailer 7£19,032 GBP
Retailer 2£19,757 GBP
Retailer 6£20,135 GBP
NZ Jewellers£23,966 GBP

20 data points across 11 retailers

11 retailers£14,901 GBP to £20,135 GBP

A
Cheapest Retailer
-
£14,901 GBP
$19,996 USD
B+
Retailer 2
-
£16,237 GBP
CA$30,262 CAD
View
Retailer 3
-
£16,917 GBP
$22,702 USD
View
Price last confirmed 8 days ago
Retailer 4
-
£17,627 GBP
$23,654 USD
View
Price last confirmed 9 days ago
Retailer 5
-
£17,763 GBP
$23,837 USD
View
Price last confirmed 8 days ago
Retailer 6
-
£18,327 GBP
$24,594 USD
View
Price last confirmed 7 days ago
B+
Retailer 7
-
£18,746 GBP
$25,156 USD
View
Retailer 8
-
£19,032 GBP
$25,540 USD
View
Price last confirmed 10 days ago
Retailer 9
-
£19,757 GBP
View
Price last confirmed 7 days ago
B
Retailer 10
-
£20,135 GBP
$27,020 USD
View
Most Expensive
NZ Jewellers
87e3a822-8f96-461c-8f32-700b8029eee0 · Oct 24
£23,966 GBP
$32,161 USD
View
Price last confirmed 9 days ago
10 more retailers have this diamond
Prices start from £14,901 GBPSave up to £5,234 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
2.51ct Marquise
£14,901 GBP