GRAPHITE PENCILS AND THEIR
GRADING
BY VIGIL ARTS AND CRAFTS
■ Graphite pencils are made
of a mixture of finely ground clay powder and graphite.
■ Their darkness varies from
black to light grey. A higher amount of clay added to the pencil makes it
harder, leaving lighter marks.
■ Artistic graphite pencils have
grading scale ranges from 9H to 9B.
The 19 degrees of graphite pencil hardness
are: 14B, 12B, 10B, 8B, 7B, 6B, 5B, 4B, 3B, 2B, B, HB, F, H, 2H, 3H, 4H,
5H, and 6H.
■ Indication and Meaning :
“H” indicate pencil hardness
“B” indicate blackness of the pencil’s
mark/lead softness
“F” indicate that the pencil’s fine point
B: Soft Black
HB: Hard Black
F: Firm
2B pencil have higher blackness, while HB have lower blackness and B have lower in harness
■ HARDNESS TEST
This “pencil hardness” test the grade of the
hardest pencil that does not permanently mark the coating, when pressed firmly
against it at a 45 degree angle. Mohs hardness testing for pencils is
another standardized measurement scale.