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Marquise|Natural|GIA

1.51ct L SI1 Marquise Natural Diamond

EX • L/SI1 • GIA 6551512143

Certificate GIA 6551512143

Diamond specifications and retailer prices

From £3,489 GBP
$4,670 USD
As of November 7, 2026
2 retailers carry this diamond
Most expensive: £3,489 GBP at Brilliant Earth
View at Brilliant Earth

About this 1.51ct natural marquise diamond

This 1.51ct natural marquise sits in the one-and-a-half to two carat band, graded L colour (faint-tinted) and SI1 clarity (slightly-included), with a top-tier cut grade stated by the retailer rather than the lab and certified by GIA 6551512143. Listed at 2 retailers as of November 7, 2026. 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

1.51
Carat
L
Colour
SI1
Clarity
Excellent
Cut (retailer stated)

Specifications

Cut (retailer stated)Excellent
PolishExcellent
SymmetryVery Good
FluorescenceFaint
Crown angle37.22°
Pavilion angle40.19°
OriginNatural
Grading LabGIA
CertificateGIA 6551512143
Dimensions11.54 × 6.03 × 3.75 mm
L/W Ratio1.91
Girdle conditionThick
Key to symbols
Crystal, Feather
Top View
11.54 mm6.03 mm1.51 ctL / SI1
OriginNatural
CutExcellent
PolishExcellent
SymmetryVery Good
FluorescenceFaint
CertificateGIA 6551512143
Side View
Table 62.0%Crown 37.22°Girdle: MED-THKPavilion 40.19°CuletDepth 62.2%

Caratlytics Score

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B
Good
Decent quality, room for better deals
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Price History

Last verified: Nov 7
Current: £3,489 GBP|Low: £2,839 GBP|High: £4,108 GBP|Avg: £3,406 GBP
Brilliant Earth
Retailer 2
Retailer 3
Retailer 4
October 31, 2026
Retailer 3£2,839 GBP
Retailer 2£3,121 GBP
Brilliant Earth£3,489 GBP
Retailer 4£4,108 GBP

9 data points across 4 retailers

2 retailers

Retailer 1
-
£2,839 GBP
Price last confirmed 17 days ago
Most Expensive
B
Brilliant Earth
22377683A · Nov 7
£3,489 GBP
$4,670 USD
View
1 more retailer has 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
1.51ct Marquise
£3,489 GBP