Round|Natural|GIA

1.21ct M SI1 Round Natural Diamond

EX • M/SI1 • GIA 5553325336

Certificate GIA 5553325336

Diamond specifications and retailer prices

From £1,237 GBP
As of November 5, 2026
Save £364 GBP (23%) vs most expensive(unlock to see where)
10 retailers carry this diamond
Most expensive: £2,869 GBP at NZ Jewellers · As of September 28, 2026
View at NZ Jewellers

About this 1.21ct natural round diamond

This 1.21ct natural round sits in the classic one-carat band, graded M colour (faint-tinted) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by GIA 5553325336. Listed at 10 retailers as of November 4, 2026, with a 29% 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

1.21
Carat
M
Colour
SI1
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceFaint
Crown angle35.5°
Pavilion angle41°
OriginNatural
Grading LabGIA
CertificateGIA 5553325336
Dimensions6.76 × 6.80 × 4.22 mm
L/W Ratio1.01
Star length50%
Culet sizeNone
Key to symbols
Crystal, Feather, Knot, Needle
Top View
6.76 mm6.80 mm1.21 ctM / SI1
OriginNatural
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceFaint
CertificateGIA 5553325336
Side View
Table 58.0%Crown 35.5°GirdlePavilion 41°Culet: NoneDepth 62.3%

Caratlytics Score

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

Price History

Last verified: Nov 5
Current: £1,435 GBP|Low: £1,176 GBP|High: £1,901 GBP|Avg: £1,415 GBP|+2.5%
Retailer 1
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
November 5, 2026
Retailer 3£1,176 GBP
Retailer 6£1,176 GBP
Retailer 5£1,237 GBP
Retailer 1£1,435 GBP
Retailer 2£1,601 GBP
Retailer 4£1,901 GBP

27 data points across 6 retailers

10 retailers£1,237 GBP to £1,601 GBP

Retailer 1
-
£1,176 GBP
Price last confirmed 29 days ago
Retailer 2
-
£1,176 GBP
View
Price last confirmed 29 days ago
Retailer 3
-
£1,231 GBP
View
Price last confirmed 38 days ago
B+
Retailer 4
-
£1,237 GBP
View
Retailer 5
-
£1,357 GBP
View
Price last confirmed 68 days ago
Retailer 6
-
£1,357 GBP
View
Price last confirmed 38 days ago
B+
Retailer 7
-
£1,435 GBP
View
B
Retailer 8
-
£1,601 GBP
View
Retailer 9
-
£2,869 GBP
View
Price last confirmed 66 days ago
Most Expensive
NZ Jewellers
942493f4-b33a-49ad-9bc0-a06af7574dbc · Sep 28
£2,869 GBP
$3,862 USD
View
Price last confirmed 39 days ago
9 more retailers have this diamond
Prices start from £1,237 GBPSave up to £364 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 Round
£1,237 GBP