PENCIL GRADE (HB and "2")

You always see a mark on pencil 'HB' or "2".

So what are 'HB' and "2" ?
There are always a grading system for the quality of every thing. Similarly there are two grading system for pencil core/lead, one is number graphite scale (or american system) and other one is HB graphite scale (or european system)

HB GRAPHITE SCALE

Here, 'H' stands for Hardness
'B' stands for bold and darkness.

To understand this first we know that Pencil core is made up of two material 'graphite' and 'clay'. Core's hardness and softness depend upon the concentration of these two materials.

Greater 'B'grade ( like 2B, 3B....) means core has more graphite and will be bolder and dark lines.

Greater 'H' grade (like 2H, 3H ...) means core has more clay and will harder but lighter and fine lines.

'F' is also used in general between 'HB' and 'H'.

NUMERICAL GRAPHITE SCALE

It is an another graphite grading scale system. Using this the hardness of core is marked on the pencil (such as "2", "2-1/2", "3").

Higher the number harder the pencil core and lighter the mark.

And smaller the number softer the pencil core and darker the mark

COMPARISON OF TWO

'HB' and "2" both are at the middle of graphite scale and have same darkness and hardness.

But pencil grading is not universal. Standards vary across companies, and across countries. Like German and Czech pencils tend to run a bit hard, U.S. and Swiss pencils tend to be more medium, and Japanese pencils run a bit soft.

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