Round|Lab Grown|IGI

1.20ct D SI1 Round Lab Grown Diamond

EX • D/SI1 • IGI LG517200392

Shape and cutting style on the report: Round brilliant

Certificate IGI LG517200392

Diamond specifications and retailer prices

From $437 USD
As of October 28, 2026
Save $1,119 USD (72%) vs most expensive(unlock to see where)
13 retailers carry this diamond
Most expensive: $1,901 USD at MOH London · As of October 29, 2026
View at MOH London

About this 1.2ct lab-grown round diamond

This 1.2ct lab-grown round sits in the classic one-carat band, graded D colour (colourless) and SI1 clarity (slightly-included), with a top-tier cut grade and certified by IGI LG517200392 or 517200392. Listed at 13 retailers as of October 24, 2026, with a 256% 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

1.20
Carat
D
Color
SI1
Clarity
Excellent
Cut

Specifications

CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle36.1°
Pavilion angle41.1°
OriginLab Grown
Grading LabIGI
CertificateIGI LG517200392
Dimensions6.74 × 6.70 × 4.23 mm
L/W Ratio1.01
Girdle conditionFaceted
Culet sizePointed
Cert comments
As Grown - No indication of post-growth treatment This Laboratory Grown Diamond was created by High Pressure High Temperature (HPHT) growth process Type II
Top View
6.74 mm6.70 mm1.20 ctD / SI1
OriginLab Grown
CutExcellent
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG517200392
Side View
Table 59.5%Crown 36.1°Girdle: MED-STKPavilion 41.1°Culet: NoneDepth 62.9%

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: Oct 28
Current: $1,901 USD|Low: $312 USD|High: $1,914 USD|Avg: $745 USD|+0.5%
MOH London
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
October 30, 2026
Retailer 11$390 USD
Retailer 3$437 USD
Retailer 14$437 USD
Retailer 6$450 USD
Retailer 5$484 USD
Retailer 12$484 USD
Retailer 8$595 USD
Retailer 10$630 USD
Retailer 7$744 USD
Retailer 13$768 USD
Retailer 2$791 USD
Retailer 9$1,358 USD
Retailer 4$1,556 USD
MOH London$1,901 USD

44 data points across 14 retailers

13 retailers$437 USD to $1,556 USD

Retailer 1
-
$390 USD
Price last confirmed 7 days ago
B+
Retailer 2
-
$437 USD
View
Final sale: no returns
B+
Retailer 3
-
$437 USD
View
B+
Retailer 4
-
$450 USD
View
B+
Retailer 5
-
$484 USD
View
Retailer 6
-
$595 USD
View
Price last confirmed 8 days ago
B+
Retailer 7
-
$630 USD
View
B
Retailer 8
-
$744 USD
€709 EUR
View
B
Retailer 9
-
$768 USD
View
B
Retailer 10
-
$791 USD
£623 GBP
View
B
Retailer 11
-
$1,358 USD
View
B
Retailer 12
-
$1,556 USD
View
Most Expensive
MOH London
LG517200392 · Oct 29
$1,901 USD
£1,497 GBP
View
Price under review
12 more retailers have this diamond
Prices start from $437 USDSave up to $1,119 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.

B+
1.20ct Round
$437 USD