| GIA |
AGS
|
SCAN
D.N.
|
CIBJO |
HRD* |
|
Main
Grades*
|
Subgrades*
|
| FL
(flawless) |
0
|
Loupe
clean
|
FL
|
Loupe
clean (lc).
Free from inclusions and bearding |
Loupe
clean.
Inclusions do not exceed 5 micron* |
|
Internally
flawless
|
1
|
IF |
VVS1
(very, very slightly included) |
VVS
|
VVS1
|
VVS*
(VVS1, VVS2)
Very, very small inclusion(s), very hard to find with a 10x
loupe |
VVS1 -
VVS2: Inclusions visible through
table have average sizes of 12 micron (VVS1),
25 micron (VVS2);
larger when visible through other facets |
VVS2
(very, very slightly included) |
2
|
VVS2
|
VS1
(very slightly included) |
3
|
VS
|
VVS1
|
VS*
(VS1, VS2)
Very small inclusion(s), which can hardly be found with a
10x loupe |
VS1 -
VS2: Inclusions visible through
table have average sizes of 40 micron (VS1),
70 micron (VS2);
larger when visible through other facets |
VS2
(very slightly included) |
4
|
VVS2
|
SI1
(slightly included) |
5
|
SI
|
SI1
|
SI
(SI1, SI2)
Small inclusion(s), easy to find with a 10x loupe, not seen
with the naked eye through the crown side |
S1. Inclusions
visible through table have average sizes of 150 micron |
SI2
(slightly included) |
6
|
SI2
|
I1
(imperfect) |
7
|
P
|
P1
|
PI
(Pique I)
Inclusion(s) immediately evident with a 10x loupe, difficult
to find with the naked eye through the crown side, not imparing
brilliance |
P1. Inclusions
which are visible through the crown-side have average
sizes of 0.5 mm |
|
8
|
I2
(imperfect) |
P2
|
PII
(Pique II)
Large and/or numerous inclusion(s), easily visible to the
naked eye through the crown side and which slightly reduce(s)
brilliance |
P2. Inclusions
have average sizes of 1.5 mm; they slightly reduce brilliancy |
|
9
|
I3
(imperfect) |
10
|
P3
|
PII
(Pique II)
Large and/or numerous inclusion(s), very easily visible to
the naked eye through the crown side and which reduce(s)
brilliance |
P3. Inclusions
have average sizes of 3 mm or larger; they reduce the
brilliancy |
| |
*
For stones under 0.47ct |
*
For stones 0.47ct and larger |
*Subdivision
of VVS and VS into two further subdivisions done only for
sizes 0.47ct and larger |
*In
conformity with IOC rules, although latter have not published
micron dimensions for grades below Loupe clean. The mentioned
size, are for bright inclusions, sizes increase for less
bright |