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Marquise|Natural|GIA

2.51ct I SI2 Marquise Natural Diamond

EX • I/SI2

Diamond specifications and retailer prices

From $28,532 AUD
$19,996 USD
As of November 2, 2026
Save $10,023 AUD (26%) vs most expensive(unlock to see where)
11 retailers carry this diamond
Most expensive: $45,891 AUD 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: $45,891 AUD|Low: $28,532 AUD|High: $45,891 AUD|Avg: $35,447 AUD
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$28,532 AUD
Retailer 5$31,091 AUD
Retailer 8$32,393 AUD
Retailer 11$33,752 AUD
Retailer 4$34,013 AUD
Retailer 10$35,093 AUD
Retailer 9$35,895 AUD
Retailer 7$36,443 AUD
Retailer 2$37,831 AUD
Retailer 6$38,555 AUD
NZ Jewellers$45,891 AUD

20 data points across 11 retailers

11 retailers$28,532 AUD to $38,555 AUD

A
Cheapest Retailer
-
$28,532 AUD
$19,996 USD
B+
Retailer 2
-
$31,091 AUD
CA$30,262 CAD
View
Retailer 3
-
$32,393 AUD
$22,702 USD
View
Price last confirmed 8 days ago
Retailer 4
-
$33,752 AUD
$23,654 USD
View
Price last confirmed 9 days ago
Retailer 5
-
$34,013 AUD
$23,837 USD
View
Price last confirmed 8 days ago
Retailer 6
-
$35,093 AUD
$24,594 USD
View
Price last confirmed 7 days ago
B+
Retailer 7
-
$35,895 AUD
$25,156 USD
View
Retailer 8
-
$36,443 AUD
$25,540 USD
View
Price last confirmed 10 days ago
Retailer 9
-
$37,831 AUD
£20,876 GBP
View
Price last confirmed 7 days ago
B
Retailer 10
-
$38,555 AUD
$27,020 USD
View
Most Expensive
NZ Jewellers
87e3a822-8f96-461c-8f32-700b8029eee0 · Oct 24
$45,891 AUD
$32,161 USD
View
Price last confirmed 9 days ago
10 more retailers have this diamond
Prices start from $28,532 AUDSave up to $10,023 AUD

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
$28,532 AUD