Grading scales
DIAMOND – INTERNAL Characteristics
IF | Internally flawles at 10 magnifications |
VVS – (VVS1, VVS2) | Very very small inclusions, very difficult to see at 10 magnifications |
VS – (VS1, VS2) | Small inclusions, difficult to see at 10 magnifications |
SI – (SI1, SI2) | Very small inclusions, easy to see at 10 magnifications |
P – (P1, P2, P3) | Inclusions which can be found with the naked eye |
DIAMOND – cut grade
PROPORTIONS | FINISH | POLISHING | FLUORESCENCE |
excellent | excellent | excellent | none |
very good | very good | very good | slight |
good | good | good | medium |
fair | fair | fair | strong |
poor | poor | poor |
DIAMOND – color scale
D E F | G H I J | K L M | N O P Q R | S T U V W X Y Z |
Colorless | Near colorless | Faint yellow | Very light yellow | Light yellow |
TREATMENTS
The following classification of the most common treatments carried out on gems is used as a reference for the drafting of the analysis documents.
Treatments other than those described, will be specifically indicated in the comments.
NTE | No indications of heating* |
TE | Indications of heating |
TE1 | Indications of heating with minor residues in fissures |
TE2 | Indications of heating with minor residues in fissures |
TE3 | Indications of heating with moderate residues in fissures |
TE4 | Indications of heating with moderate residues in fissures |
TE5 | Indications of heating with significant residues in fissures |
F1 | Minor presence of foreign substances in fissures |
F2 | Moderate presence of foreign substances in fissures |
F3 | Significant presence of foreign substances in fissures |
CR1 | Minor presence of foreign material in cavities |
CR2 | Moderate presence of foreign material in cavities |
CR3 | Significant presence of foreign material in cavities |
*The lack of diagnostic elements (NTE) for the determination of heat treatment does not absolutely guarantee that
the gem in question has not been subjected to this process.