Professional Diamond Grading System

Comprehensive Reference Chart for Diamond Quality Assessment

Diamond Shapes

Round

Oval

Pear

Marquise

Heart

Cushion

Cushion B

Emerald

Princess

Sq Radiant

L Radiant

Other

Carat

30s Down

30s

40s

50s-60s

70s-80s

90s

1ct

1.5ct

2ct

3ct-4ct

5ct

5ct - 99.99ct

Clarity

FL

IF

VVS1

VVS2

VS1

VS2

SI1

SI2

SI3

I1

I2

I3

Color

D

E

F

G

H

I

J

K

L

M

N

O-P

Q-R

W-X

Y-Z

Cut

EX	VG	GD	F
Excellent	Very Good	Good	Fair

Polish

EX	VG	GD	F
Excellent	Very Good	Good	Fair

Symmetry

EX	VG	GD	F
Excellent	Very Good	Good	Fair

White Inclusion Base (WT)

N(WT0)	NV	WT1	WT2	WT3
None	None Visible	Minor	Medium	Major

Black Inclusion Base (BT)

N(BT0)	NV	BT1	BT2	BT3
None	None Visible	Minor	Medium	Major

Milky

N(M0)	NV	M1	M2	M3
None	None Visible	Minor	Medium	Major

Open Base

Grade	NW (NO-WHITE)	MV	CO1	CO2	CO3	CO4
Inc. Eye	Open	Open	Open	Open	Open	Open
Location	None	Visible	Cone	Cone	Cone	Cone
Description	None	None	None Visible	None	None	None

Fluorescence

FL Grade	N	FNT	MED	STG	VST
Description	None Fluorescence	Faint Fluorescence	Medium Fluorescence	Strong Fluorescence	Very Strong Fluorescence

Color Shade

Grade	N	MV	BRN1	BRN2	BRN3
Color Shade	WHITE-WHITE	Brown/Gray/Pink	Brown	Light	Dark
Description	None Visible		Faint	Light	Dark

Eye Clean

Grade	EC1	EC2	IC1	IC2	V
%	75% - 100%	50% - 75%	25% - 50%	0% - 25%	Visible
Description	Sea	Medium	Medium	Include Visible	Visible

Heart & Arrow Base

Grade	HA1	HA2	HA3	HA4	V
Description	LG H&A	VG H&A	None Visible

Lab

GIA	IGI	HRD	IGI2	AGS	NONE	FM	FM2	FM3
Gemological Institute of America	International Gemological Institute	High Council for Diamonds	IGI2	American Gem Society	No Certificate	Forever Mark Grading	Forever Mark Eligible	Forever Mark Inscribed

Rough Origin

Canada Mine	Canada Mine Eligible	Other	None	Forever Mark Grading	Forever Mark Eligible	Forever Mark Inscribed
Canada Mine	Canada Mine Eligible		None	Forever Mark Grading	Forever Mark Eligible	Forever Mark Inscribed