Gizmodo reports that a stainless steel metal pen writes without using any ink. The 'nib' of the pen is a metal alloy that leaves a pencil-like mark when the pen is used on paper. The Grand Illusions website explains how the pen works.
In the Medieval period, artists and scribes often used a metal stylus in order to draw on a specially prepared paper surface. Generally known as Metalpoint, or Silverpoint when the stylus was made of silver, artists such as Leonardo da Vinci, Dürer and Rembrandt all used this technique. http://www.silverpointweb.com/index.html gives a lot of information about how it works.
The pens we sell are a modern version (and do not use silver). The solid metal 'nib' consists of a metal alloy, that leaves a mark on most types of paper. If you use the sort of paper typically used in printers and photocopiers, the pen leaves a mark that looks as if it was made by a pencil. However the line will not smudge, and cannot be rubbed out.
Since there is no ink, there is nothing to dry out, so the pen will work just as well in 25 years time as it does today. And of course it never needs sharpening!
Gizmodo 
