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In the 16th century, shepherds high up in the Scottish mountains found a previously unkown material that shone like lead ore. Wooden or metal tong-like appliances with pieces of this material wedged in were soon in use as a new kind of writing instrument. This innovation became misleadingly known as the lead pencil.
It wasn't until 1789 that a Swedish chemist was able to prove that the material in question was not actually lead, but a form of crystallised carbon, or graphite.
This rare, and therefore rather expensive, graphite was mixed with sulphur and clay (later with synthetics too). By varying the recipe, various degrees of hardness could be achieved at kiln temperatures of around 1,100 degrees centigrade
As early as the beginning of the 19th century, there were already pencils on the market that weren't encased in wood. They had a twist mechanism for advancing the graphite lead forwards to the writing tip. Up until the first world war, it was standard practice for these early mechanical pencils to hold a single piece of lead with a 2mm diameter. The mechanical pencil lead - also known as fineline lead - is a relatively new invention which originates from traditional pencil lead.
While working on the development of STAEDTLER mechanical pencil leads, chemists discovered that carbon fibre had a number of advantages to offer - it is very light in weight at the same time as being extremely resilient and pliable. Carbon fibre is primarily used as a reinforcing material in the aeronautic industry. Back in 1880, Edison was the first man to succeed in coking strands of cellulose and he developed carbon filaments out of them for his electric light bulb invention. Just as was the case with the first mechanical pencil leads almost 100 years later, this early carbon fibre was neither particularly stable, nor was it very flexible.
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