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Radiant|Natural|GIA

0.51ct H SI1 Radiant Natural Diamond

ID • H/SI1 • GIA 6551775683

Certificate GIA 6551775683

Diamond specifications and retailer prices

From $820 AUD
HK$4,500 HKD
As of October 27, 2026
Save $353 AUD (30%) vs most expensive(unlock to see where)
10 retailers carry this diamond
Most expensive: $2,101 AUD at MOH London · As of October 25, 2026
View at MOH London

About this 0.51ct natural radiant diamond

This 0.51ct natural radiant sits in the half to three-quarter carat band, graded H colour (near-colourless) and SI1 clarity (slightly-included), with a top-tier cut grade stated by the retailer rather than the lab and certified by GIA 6551775683. Listed at 10 retailers as of October 26, 2026, with a 43% 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

0.51
Carat
H
Colour
SI1
Clarity
Ideal
Cut (retailer stated)

Specifications

Cut (retailer stated)Ideal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle35.6°
Pavilion angle60.92°
OriginNatural
Grading LabGIA
CertificateGIA 6551775683
Dimensions5.36 × 4.02 × 2.71 mm
L/W Ratio1.33
Culet sizeNone
Top View
5.36 mm4.02 mm0.51 ctH / SI1
OriginNatural
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateGIA 6551775683
Side View
Table 66.0%Crown 35.6°Girdle: Very ThickPavilion 60.92°Culet: NDepth 67.3%

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: Oct 27
Current: $2,101 AUD|Low: $609 AUD|High: $2,349 AUD|Avg: $1,153 AUD|+9.2%
MOH London
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
October 26, 2026
Retailer 8$733 AUD
Retailer 11$755 AUD
Retailer 9$759 AUD
Retailer 7$820 AUD
Retailer 6$971 AUD
Retailer 2$1,062 AUD
Retailer 10$1,173 AUD
Retailer 4$1,287 AUD
Retailer 5$1,330 AUD
Retailer 3$1,445 AUD
MOH London$2,101 AUD

36 data points across 11 retailers

10 retailers$820 AUD to $1,173 AUD

Retailer 1
-
$733 AUD
$515 USD
Price last confirmed 10 days ago
Retailer 2
-
$755 AUD
$530 USD
View
Price last confirmed 8 days ago
A
Retailer 3
-
$820 AUD
HK$4,500 HKD
View
Retailer 4
-
$971 AUD
$682 USD
View
Price last confirmed 7 days ago
Retailer 5
-
$1,062 AUD
£587 GBP
View
Price last confirmed 7 days ago
B+
Retailer 6
-
$1,173 AUD
$824 USD
View
Retailer 7
-
$1,287 AUD
£712 GBP
View
Price last confirmed 7 days ago
Retailer 8
-
$1,330 AUD
€890 EUR
View
Price last confirmed 8 days ago
Retailer 9
-
$1,445 AUD
View
Price last confirmed 29 days ago
Most Expensive
MOH London
BDEDAD885 · Oct 25
$2,101 AUD
£1,162 GBP
View
Price last confirmed 8 days ago
9 more retailers have this diamond
Prices start from $820 AUDSave up to $353 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
0.51ct Radiant
$820 AUD