Round|Natural|GIA

1.28ct I SI1 Round Natural Diamond

EX • I/SI1 • GIA 3555600029

Certificate GIA 3555600029

Diamond specifications and retailer prices

From $2,659 USD
As of November 6, 2026
Save $3,556 USD (57%) vs most expensive(unlock to see where)
21 retailers carry this diamond
Most expensive: $6,215 USD at NZ Jewellers · As of November 5, 2026
View at NZ Jewellers

About this 1.28ct natural round diamond

This 1.28ct natural round sits in the one-and-a-quarter to one-and-a-half carat band, graded I colour (near-colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by GIA 3555600029. Listed at 21 retailers as of November 5, 2026, with prices from $2,659 to $6,215, a $3,556 spread on the same certified stone. NZ Jewellers lists it at $6,215. 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

1.28
Carat
I
Color
SI1
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle35°
Pavilion angle40.8°
OriginNatural
Grading LabGIA
CertificateGIA 3555600029
Dimensions6.94 × 6.97 × 4.27 mm
L/W Ratio1.00
Culet sizeNone
Key to symbols
Twinning Wisp, Cloud, Crystal, Feather, Needle, Indented Natural
Top View
6.94 mm6.97 mm1.28 ctI / SI1
OriginNatural
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateGIA 3555600029
Side View
Table 58.0%Crown 35°Girdle: MED-STKPavilion 40.8°Culet: NoneDepth 61.4%

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: $2,659 USD|Low: $2,659 USD|High: $6,028 USD|Avg: $3,830 USD|-2.4%
Retailer 1
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
November 6, 2026
Retailer 1$2,659 USD
Retailer 7$2,662 USD
Retailer 9$3,065 USD
Retailer 2$3,413 USD
Retailer 3$3,669 USD
Retailer 8$3,805 USD
Retailer 4$4,144 USD
Retailer 5$4,354 USD
Retailer 6$5,949 USD

26 data points across 9 retailers

21 retailers$2,659 USD to $6,215 USD

A
Cheapest Retailer
-
$2,659 USD
A
Retailer 2
-
$2,662 USD
View
A
Retailer 3
-
$3,065 USD
View
A
Retailer 4
-
$3,167 USD
View
A
Retailer 5
-
$3,292 USD
View
Final sale: no returns
A
Retailer 6
-
$3,413 USD
View
A
Retailer 7
-
$3,430 USD
View
Retailer 8
-
$3,567 USD
View
Price last confirmed 8 days ago
B+
Retailer 9
-
$3,567 USD
View
A
Retailer 10
-
$3,669 USD
View
B+
Retailer 11
-
$3,703 USD
View
B+
Retailer 12
-
$3,704 USD
View
B+
Retailer 13
-
$3,712 USD
View
B+
Retailer 14
-
$3,805 USD
View
Retailer 15
-
$3,820 USD
View
Price last confirmed 29 days ago
B+
Retailer 16
-
$4,116 USD
View
B+
Retailer 17
-
$4,144 USD
View
B+
Retailer 18
-
$4,354 USD
View
B
Retailer 19
-
$5,949 USD
View
Retailer 20
-
$6,058 USD
View
Price last confirmed 66 days ago
Most Expensive
B
NZ Jewellers
3a3018ef-e528-4962-97d6-8518516e0f75 · Nov 5
$6,215 USD
View
20 more retailers have this diamond
Prices start from $2,659 USDSave up to $3,556 USD

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
1.28ct Round
$2,659 USD