The pencil is he most popular element when it comes to 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 annotations 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 XVII in England where a very important deposit of graphite was discovered. Although England dominated the pencil-making business for many years, the emergence of a brand-new method by which graphite powder could be made expanded its trade. Meanwhile, it would be in Italy where the idea of adding a wooden support to graphite pencils would arise.
Towards the middle of 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 mistake made in writing or drawing.
Today pencils are made by combining graphite powder with ground clay. Water is added to the mixture, which will form elongated mines that are then cooked in the oven. The result is dipped in wax or oil, which is what will give the writing a smooth finish. Next, a cedar plank is cut to make a lath and the clay and graphite strips are inserted into it. One more ribbed looking plank will be laid on the surface and finally varnished or painted.
There is a pencil grading system that measures its hardness and dark coloration. The letter H designates the hardness, while the letter B designates the degree of darkness that they present.
