Round|Natural|GIA

1.00ct K SI1 Round Natural Diamond

EX • K/SI1 • GIA 240

Certificate GIA 240

Diamond specifications and retailer prices

From £977 GBP
As of November 5, 2026
Save £1,406 GBP (59%) vs most expensive(unlock to see where)
11 retailers carry this diamond
Most expensive: £2,572 GBP at NZ Jewellers · As of September 25, 2026
View at NZ Jewellers

About this 1ct natural round diamond

This 1ct natural round sits in the classic one-carat band, graded K colour (faint-tinted) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by GIA. Listed at 11 retailers as of November 5, 2026, with a 144% 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

1.00
Carat
K
Colour
SI1
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
OriginNatural
Grading LabGIA
CertificateGIA 240
Dimensions6.46 × 6.50 × 3.91 mm
L/W Ratio1.01
Top View
6.46 mm6.50 mm1.00 ctK / SI1
OriginNatural
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateGIA 240
Side View
Table 59.0%CrownGirdle: THN-MEDPavilionCulet: NoneDepth 60.2%

Caratlytics Score

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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 5
Current: £2,384 GBP|Low: £977 GBP|High: £2,572 GBP|Avg: £1,338 GBP|-7.3%
NZ Jewellers
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
October 24, 2026
Retailer 2£977 GBP
Retailer 4£977 GBP
Retailer 5£999 GBP
Retailer 3£1,022 GBP
Retailer 6£1,128 GBP
Retailer 7£1,236 GBP
Retailer 8£1,267 GBP
Retailer 9£1,484 GBP
NZ Jewellers£2,384 GBP

18 data points across 9 retailers

11 retailers£977 GBP to £2,384 GBP

A
Cheapest Retailer
-
£977 GBP
Retailer 2
-
£977 GBP
View
Price last confirmed 8 days ago
A
Retailer 3
-
£999 GBP
View
A
Retailer 4
-
£1,022 GBP
View
Retailer 5
-
£1,054 GBP
View
Price last confirmed 43 days ago
A
Retailer 6
-
£1,128 GBP
View
Retailer 7
-
£1,217 GBP
View
Price last confirmed 45 days ago
Retailer 8
-
£1,236 GBP
View
Price last confirmed 30 days ago
Retailer 9
-
£1,267 GBP
View
Price last confirmed 30 days ago
B
Retailer 10
-
£2,384 GBP
View
Most Expensive
NZ Jewellers
cc9b158d-30ec-4b7a-8bf3-4d1f069758aa · Sep 25
£2,572 GBP
$3,462 USD
View
Price last confirmed 42 days ago
10 more retailers have this diamond
Prices start from £977 GBPSave up to £1,406 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.

A
1.00ct Round
£977 GBP