What other number pencils are there

Generally, an HB grade about the middle of the scale is considered to be equivalent to a 2 pencil using the U. In reality however, there is no specific industry standard for the darkness of the mark to be left within the HB or any other hardness grade scale.

Thus, a 2 or HB pencil from one brand will not necessarily leave the same mark as a 2 or HB pencil from another brand. Most pencil manufacturers set their own internal standards for graphite hardness grades and overall quality of the core, some differences are regional.

In Japan, consumers tend to prefer softer darker leads, so an HB lead produced in Japan is generally softer and darker than an HB from European producers. Finding what works best for your own artistic and writing needs is generally a matter of personal preference and experimentation with different brands of pencils. They were also painted yellow, which was unusual at the time. Some historians claim that the Austrian company painted their pencils yellow as a subtle nod to the yellow on the flag of Austria-Hungary.

Others claim the yellow was an even subtler nod to the Far Eastern graphite in the pencils; the color yellow is associated with royalty in China.

In either case, the new yellow pencils were a hit, and soon other companies began painting their own wares yellow in an attempt to swipe some of Hardtmuth's business. It sure does. You bet. According to records from the 18th century, the elastic substance from tropical plants got its name thanks to its common use of being rubbed over pencil marks to erase them.

Since using this substance as an eraser required a lot of rubbing, people began calling it rubber. If you owned a pencil sharpener in early 20th century England, you had a hot little piece of contraband. At the time, the supply of the red cedar that had historically been used in pencils was getting perilously low, so the government briefly outlawed pencil sharpeners in order to limit waste from overzealous sharpening.

Eventually the mechanical pencil and the discovery of incense-cedar's usefulness in making pencils solved this problem, and pencil sharpeners became street legal once again. BY Ethan Trex. Big Questions History News writing. Subscribe to our Newsletter! Today, many U. For graphic and artist pencils and for companies outside the U. Lowest on the scale is 9H, indicating a pencil with extremely hard lead that produces a light mark.

On the opposite end of the scale, 9B represents a pencil with extremely soft lead that produces a dark mark. So why are testing centers such sticklers about using only No. They cooperate better with technology because early machines used the electrical conductivity of the lead to read the pencil marks. Early scanning-and-scoring machines couldn't detect marks made by harder pencils, so No.