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Marquise|Natural|GIA

1.21ct J SI1 Marquise Natural Diamond

GD • J/SI1 • GIA 2554338825

Certificate GIA 2554338825

Diamond specifications and retailer prices

From £1,931 GBP
As of October 31, 2026
Save £1,668 GBP (46%) vs most expensive(unlock to see where)
14 retailers carry this diamond
Most expensive: £3,600 GBP at Helzberg Diamonds · As of November 3, 2026
View at Helzberg Diamonds

About this 1.21ct natural marquise diamond

This 1.21ct natural marquise sits in the classic one-carat band, graded J colour (near-colourless) and SI1 clarity (slightly-included), with a standard cut grade stated by the retailer rather than the lab and certified by GIA 2554338825. Listed at 14 retailers as of October 31, 2026, with prices from £1,931 to £3,600, a £1,668 spread on the same certified stone. Helzberg Diamonds lists it at £3,600. Cut grade matters more than carat or clarity for visible brilliance. If you can shift budget toward an Excellent or Ideal cut, do it before chasing higher colour or clarity.

The 4Cs

1.21
Carat
J
Colour
SI1
Clarity
Good
Cut (retailer stated)

Specifications

Cut (retailer stated)Good
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle43.87°
Pavilion angle39.78°
OriginNatural
Grading LabGIA
CertificateGIA 2554338825
Dimensions9.83 × 5.39 × 3.60 mm
L/W Ratio1.82
Culet sizeNone
Top View
9.83 mm5.39 mm1.21 ctJ / SI1
OriginNatural
CutGood
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateGIA 2554338825
Side View
Table 59.0%Crown 43.87°Girdle: STK-VTKPavilion 39.78°Culet: NoneDepth 66.6%

Caratlytics Score

How it works →
B+
Very Good
Strong quality and value balance
Unlock full score analysis
See the detailed 0 to 100 score with Quality, Value, Certification & Market breakdown

Price History

Last verified: Oct 31
Current: £3,600 GBP|Low: £1,931 GBP|High: £3,825 GBP|Avg: £2,585 GBP|-5.9%
Helzberg Diamonds
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Retailer 12
Retailer 13
November 5, 2026
Retailer 4£1,931 GBP
Retailer 2£1,978 GBP
Retailer 9£2,078 GBP
Retailer 5£2,101 GBP
Retailer 6£2,238 GBP
Retailer 13£2,280 GBP
Retailer 11£2,445 GBP
Retailer 3£2,475 GBP
Retailer 12£2,520 GBP
Retailer 8£2,524 GBP
Retailer 7£3,193 GBP
Retailer 10£3,399 GBP
Helzberg Diamonds£3,600 GBP

40 data points across 13 retailers

14 retailers£1,931 GBP to £3,600 GBP

B+
Cheapest Retailer
-
£1,931 GBP
B+
Retailer 2
-
£1,978 GBP
View
B+
Retailer 3
-
£2,078 GBP
View
B+
Retailer 4
-
£2,101 GBP
View
B+
Retailer 5
-
£2,238 GBP
View
B
Retailer 6
-
£2,280 GBP
View
B
Retailer 7
-
£2,445 GBP
View
B
Retailer 8
-
£2,475 GBP
View
B
Retailer 9
-
£2,520 GBP
View
B
Retailer 10
-
£2,524 GBP
View
B
Retailer 11
-
£2,739 GBP
View
B
Retailer 12
-
£3,193 GBP
View
B
Retailer 13
-
£3,399 GBP
View
Most Expensive
B
Helzberg Diamonds
XZRILLKJJOOIL · Nov 3
£3,600 GBP
$4,818 USD
View
13 more retailers have this diamond
Prices start from £1,931 GBPSave up to £1,668 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.

B+
1.21ct Marquise
£1,931 GBP