I have a friend who makes and sells lead pencils... made from real lead! I know that a lot of people these days are all taboo about anything containing lead. I have no such fears. I did a little digging and came across these extant pencils.
Unique ID: IOW-946291
Unique ID: IOW-ED968C
Unique ID: IOW-6FEA87
I decided to make my own version. I started by slicing a couple pieces of green soap stone. I drilled and set register pins. I then clamped the two halves together and used a drill to rough out the shape of the pencil.
I used some small carving tools to clean up the mold but not much work was needed other than to shape the point.
I then took a collection of old fishing weights and melted them down. Note that I DID do this outside. I put a wind sheild up and simply heated the lead with a propane torch.
I didn't do any filing on these. I took a small hammer and cleaned up the tip and the cast lines by tapping the pencil with a hammer. Sharpening with a knife removes material. These pencils can be "sharpened" with a small hammer instead. The finished pencils are about 3 inches in length.