How Green Is Your Pencil?

[xoxoxoBruce]

Originally Posted by glatt

Interesting. This goes against my experience. I have handled plenty of lead, and it was all kind of dirty, but shiny just underneath.

Originally Posted by footfootfoot

And the shininess oxides rapidly, so it would make the line dark rather quickly. See the wiki link for 'splanation.

Take a pot of melted lead, the surface is all gray and crappy looking from the oxide. Now skim that oxide with a ladle, ooh, it's all shiny looking. But by the time you get the ladle all the way across the pot, and dump the oxide, the surface has gone gray again. It happens less quickly to solid lead, of course, but it won't be shiny very long.

Now if you write with lead oxide, the line won't be black like graphite, but gray. Strangely, if you write with it in Canada it won't be gray, but grey.

[glatt]

So with all this talk, I figured I'd look into the pencil and lead relationship.

According to wikipedia (I know, I know) graphite has been used in pencils since somewhere in the 1500's and 1600's.

Wikipedia claims that actual lead was never used in pencils, but there is no citation for that.

There is a mention of lead styluses being used on papyrus, but there is also no citation given for that.

But the interesting thing is that Wikipedia says that when graphite was discovered in the 1500's, the primitive chemists back then thought it was a form of lead. So they called graphite "lead." That's why pencils are said to have lead. It's simple ignorance passed down over the centuries.

[footfootfoot]

Originally Posted by glatt

It's simple ignorance passed down over the centuries.

Well, it's not the first time that has happened.