He pencil is he most widespread element when drawing and writingTherefore, it turns out to be a basic and extremely necessary tool for students of different subjects, since from it they can make notes of the classes they attend and then review the contents learned.
Generally, it is made of a graphite rod contained within a wooden or metal cylinder.
The origin of this element dates back to the century 17th in England where a very important deposit of graphite was discovered. Although England dominated the pencil manufacturing business for many years, the appearance of a new method from which it was possible to obtain graphite powder expanded its trade. Meanwhile, it would be Italy where the idea of adding a wooden support to the graphite pencils would arise.
Towards the middle of the XIX century a rubber is created that is used as an eraser to be added to the opposite end of the pencil; a design that by the way to this day is extremely practical to immediately erase that error made in writing or drawing.
Currently, pencils are made from the combination of graphite powder with ground clay. Water is added to the mixture that will form elongated mines that are then cooked in the oven. The result is submerged in wax or oil, which is what will give a smooth finish to the writing. Then, a cedar plank is cut to make the lath and the clay and graphite strips are inserted into it. One more plank with a grooved appearance will be placed on the surface and finally varnished or painted.
There is a pencil grading system that measures their hardness and dark coloration. The letter H designates the hardness, while the B the degree of darkness that they present.
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