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Radiant|Lab Grown|IGI

12.78ct F SI1 Radiant Lab Grown Diamond

ID • F/SI1 • IGI LG591336712

Shape and cutting style on the report: Cut cornered rectangular modified brilliant

Certificate IGI LG591336712

Diamond specifications and retailer prices

From HK$11,949 HKD
£1,199 GBP
As of November 2, 2026
Save HK$15,936 HKD (57%) vs most expensive(unlock to see where)
13 retailers carry this diamond
Most expensive: HK$85,868 HKD at Adiamor · As of November 2, 2026
View at Adiamor

About this 12.78ct lab-grown radiant diamond

This 12.78ct lab-grown radiant sits in the over five carat band, graded F colour (colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG591336712 or 591336712. Listed at 13 retailers as of November 1, 2026, with a 133% 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

12.78
Carat
F
Colour
SI1
Clarity
Ideal
Cut

Specifications

CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle44.8°
Pavilion angle34°
OriginLab Grown
Grading LabIGI
CertificateIGI LG591336712
Dimensions16.82 × 11.37 × 7.51 mm
L/W Ratio1.48
Cert comments
This Laboratory Grown Diamond was created by Chemical Vapor Deposition (CVD) growth process and may include post-growth treatment Type IIa
Top View
16.82 mm11.37 mm12.78 ctF / SI1
OriginLab Grown
CutIdeal
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG591336712
Side View
Table 65.0%Crown 44.8°Girdle: Slightly ThickPavilion 34°Culet: NoneDepth 66.1%

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: Nov 2
Current: HK$85,868 HKD|Low: HK$11,949 HKD|High: HK$179,550 HKD|Avg: HK$49,744 HKD|-52.2%
Adiamor
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Retailer 12
Retailer 13
Retailer 14
Retailer 15
Retailer 16
November 2, 2026
Retailer 9HK$11,949 HKD
Retailer 6HK$12,828 HKD
Retailer 5HK$13,958 HKD
Retailer 13HK$14,876 HKD
Retailer 14HK$16,202 HKD
Retailer 16HK$17,475 HKD
Retailer 15HK$19,607 HKD
Retailer 10HK$20,909 HKD
Retailer 11HK$23,397 HKD
Retailer 2HK$23,611 HKD
Retailer 12HK$25,649 HKD
Retailer 3HK$27,885 HKD
Retailer 4HK$47,744 HKD
AdiamorHK$85,868 HKD
Retailer 7HK$160,849 HKD
Retailer 8HK$161,237 HKD

7 data points across 16 retailers

13 retailersHK$11,949 HKD to HK$27,885 HKD

A
Cheapest Retailer
-
HK$11,949 HKD
£1,199 GBP
A
Retailer 2
-
HK$12,828 HKD
$1,635 USD
View
A
Retailer 3
-
HK$13,958 HKD
$1,779 USD
View
A
Retailer 4
-
HK$14,876 HKD
$1,896 USD
View
A
Retailer 5
-
HK$16,202 HKD
$2,065 USD
View
B+
Retailer 6
-
HK$17,475 HKD
View
B+
Retailer 7
-
HK$19,607 HKD
$2,499 USD
View
B+
Retailer 8
-
HK$20,909 HKD
£2,098 GBP
View
B+
Retailer 9
-
HK$23,397 HKD
$2,982 USD
View
B+
Retailer 10
-
HK$23,611 HKD
€2,866 EUR
View
B+
Retailer 11
-
HK$25,649 HKD
$3,269 USD
View
B
Retailer 12
-
HK$27,885 HKD
$3,554 USD
View
Most Expensive
Adiamor
D-82832577 · Nov 2
HK$85,868 HKD
$10,944 USD
View
Price under review
12 more retailers have this diamond
Prices start from HK$11,949 HKDSave up to HK$15,936 HKD

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
12.78ct Radiant
HK$11,949 HKD