Among pencils, special purpose, first of all, it should be noted indelible pencil and pencils for use on various surfaces paperless - a pencil on glass, porcelain, ceramics and carpentry pencils. Obviously, these pencils are called special because they were designed for the specific needs of a particular area.
Scope of pencils on glass, ceramics and other surfaces, perhaps, a little wider than they are widely used in construction, manufacturing, slightly less in the arts and crafts, for example, to apply the basics of drawing. Depending on the chosen surface or a pencil hardness level. Pencils for marking glass also called polymer pencils.