Radiant|Lab Grown|IGI

1.28ct D SI1 Radiant Lab Grown Diamond

VG • D/SI1 • IGI LG817638986

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

Certificate IGI LG817638986

Diamond specifications and retailer prices

From $1,280 USD
As of October 28, 2026
11 retailers carry this diamond
Most expensive: $1,280 USD at Brilliant Earth
View at Brilliant Earth

About this 1.28ct lab-grown radiant diamond

This 1.28ct lab-grown radiant sits in the one-and-a-quarter to one-and-a-half carat band, graded D colour (colourless) and SI1 clarity (slightly-included), with a very-good cut grade and certified by IGI LG817638986 or 817638986. Listed at 11 retailers as of October 28, 2026. 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

1.28
Carat
D
Color
SI1
Clarity
Very Good
Cut

Specifications

CutVery Good
PolishExcellent
SymmetryExcellent
FluorescenceNone
Crown angle42.6°
Pavilion angle35.4°
OriginLab Grown
Grading LabIGI
CertificateIGI LG817638986
Dimensions7.82 × 5.26 × 3.65 mm
L/W Ratio1.49
Cert comments
This Laboratory Grown Diamond was created by Chemical Vapor Deposition (CVD) growth process Type IIa
Top View
7.82 mm5.26 mm1.28 ctD / SI1
OriginLab Grown
CutVery Good
PolishExcellent
SymmetryExcellent
FluorescenceNone
CertificateIGI LG817638986
Side View
Table 66.0%Crown 42.6°Girdle: Slightly ThickPavilion 35.4°Culet: NoneDepth 69.4%

Caratlytics Score

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B
Good
Decent quality, room for better deals
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Price History

Last verified: Oct 28
Current: $1,280 USD|Low: $114 USD|High: $1,310 USD|Avg: $534 USD|-2.3%
Brilliant Earth
Retailer 2
Retailer 3
Retailer 4
Retailer 5
Retailer 6
Retailer 7
Retailer 8
Retailer 9
Retailer 10
Retailer 11
Retailer 12
October 23, 2026
Retailer 12$167 USD
Retailer 4$252 USD
Retailer 5$313 USD
Retailer 2$350 USD
Retailer 9$383 USD
Retailer 11$476 USD
Retailer 10$515 USD
Retailer 8$631 USD
Retailer 3$652 USD
Retailer 7$700 USD
Retailer 6$872 USD
Brilliant Earth$1,280 USD

31 data points across 12 retailers

11 retailers

Retailer 1
-
$252 USD
Price last confirmed 10 days ago
Retailer 2
-
$313 USD
£246 GBP
View
Price last confirmed 9 days ago
Retailer 3
-
$350 USD
€333 EUR
View
Price last confirmed 7 days ago
Retailer 4
-
$383 USD
£302 GBP
View
Price last confirmed 8 days ago
Retailer 5
-
$476 USD
View
Price last confirmed 7 days ago
Retailer 6
-
$515 USD
View
Price last confirmed 9 days ago
Retailer 7
-
$631 USD
View
Price last confirmed 9 days ago
Retailer 8
-
$652 USD
View
Price last confirmed 10 days ago
Retailer 9
-
$700 USD
View
Price last confirmed 12 days ago
Retailer 10
-
$872 USD
£687 GBP
View
Price last confirmed 10 days ago
Most Expensive
B
Brilliant Earth
20775780A · Oct 28
$1,280 USD
View
10 more retailers have this diamond

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
1.28ct Radiant
$1,280 USD