Steve wrote:

I've always assumed they used real lead at one time or that name
would
have never been used. I wonder how long ago real lead was last used?


Real lead was never used. Apparently pure graphite was intially
referred to as "plumbago"--black lead-- because people thought it was a
form of lead.
Apparently the thinking was something like this"...hmmm, soft, heavy,
black, sort of greasy feeling, must be lead."

Chemistry wasn't an exact science back then.

J. Del Col