Good thing–since the best mines (Borrowdale in the Lake District and the Alibert mine in Siberia) have been worked out, top quality native graphite is pretty much unavailable. The best ceramic leads are generally held to approach the quality of the best native graphite leads, but at much lower cost. The entire process can take several weeks, but the resulting ceramic lead is far superior to the earlier sulfur-and-graphite lead. The mixture is then shaped, dried and fired in a kiln at around 1000° C. First the graphite is ground to a fine dust, washed in water, and thoroughly mixed with high quality washed clay and water. Conté’s process is still used today for making almost all pencil leads, with only minor changes since his time. In 1795, when good pencils weren’t available in France because of the English blockade, a French scientist named Nicholas-Jacques Conté invented a new process to make good quality pencil leads from poor quality graphite. But the results were less than satisfactory. These pencils weren’t cheap, so sometimes substitutes were made with low-quality graphite from other regions, ground into a powder, mixed with a binder such as molten sulfur or glue, and allowed to harden. For a long time, the only graphite of quality high enough to be used this way came from the Lake District of England. At first all graphite pencil leads were made from native graphite (graphite as it comes out of the ground), cut into long thin pieces. One ranged from HH (extra hard) to SS (extra soft) and a variation ran from VVVH (very very very hard) to VVVS (very very very stupid–er, soft).Īll these grading systems were made possible by the modern manufacturing process that allows reproducible variation in lead hardness. Over the years, other grading systems have also been used. (Now you know why many #2 pencils are also marked HB.) The anomalous F grade is of questionable origin and may stand for “fine,” “fine point,” or “firm,” depending on which source you believe. HB stands for “hard” and “black” because it is a good compromise between the two qualities. In the middle of the scale are the grades corresponding to the number grades for inexpensive writing pencils: B = #1, HB = #2, F = #2.5, H = #3 and 2H = #4. The black end of the scale is popular for sketching, the hard end for drafting. (One might have thought it’d be less confusing to use a pairing like hardness and softness, but we weren’t consulted.) The numbers indicate degree of hardness or blackness, so 8H is harder than 7H, for example. In this system, B stands for “black” and H for "hard," blackness and hardness representing the opposite ends of the grading scale. This latter system encompasses a much wider variety of hardnesses, from 9B (much softer and darker than #1) to 10H (much harder and lighter than #4). for high-quality drafting and drawing pencils, which are usually sold individually or in sets of assorted grades, usually without erasers attached. A different system is more popular in other parts of the world and is also used in the U.S. Even in America, it’s used mostly for inexpensive general-purpose writing pencils, which are typically sold by the dozen and have attached erasers. The #3 and #4 pencils are harder and lighter yet, and even less popular for everyday writing.īut that’s only one grading system, and it’s not very common outside the U.S. It is often recommended for taking stenographic notes because it requires less frequent sharpening. The #2.5 pencil is harder than the #2, but it’s not as popular because it leaves a lighter mark that some people find hard to read. It is sometimes recommended for writing on the backs of photographs because it leaves a readable mark without requiring as much potentially damaging pressure as harder leads. The #1 pencil has the softest and darkest lead, but most people find that it smudges too easily and needs resharpening too often to make it appropriate for everyday writing. There’s a trade-off between hardness and darkness (in pencil leads I mean), and the #2 is the best compromise for most purposes. It’s called #2 because it’s the second darkest of the four major grades of pencil marketed under this system. For as long as pencils have been available in different grades, the #2 or its equivalent has been the most popular for general use. Some people believe that the #2 pencil is so called because it used to be the second most common, but that’s not the case. What else would the mathematician use to work out his calculus problem?Īll joking aside–did you miss the joking?–there are #1 pencils, and #2.5, #3, and #4 and sometimes other intermediate grades, and you can buy them all at finer stationery stores everywhere (and now online too). Of course there’s such a thing as a #1 pencil. Dear Straight Dope: What exactly is a #2 pencil and why isn’t there a #1 pencil? Jason Fanguy
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