what kind of clay do car designers use
Industrial plasticine Industrial plasticine is a modeling material which is mainly used by automotive design studios. It was developed as an industrial version of plasticine or hobby clay.
Graphite From the 16th century, all pencils were made with leads of English natural graphite, but modern pencil lead is most commonly a mix of powdered graphite and clay; it was invented by Nicolas-Jacques Conté in 1795.[39][40] It is chemically unrelated to the metal lead, whose ores had a similar appearance, hence the continuation of the name. Plumbago is another older term for natural graphite used for drawing, typically as a lump of the mineral without a wood casing. The term plumbago drawing is normally restricted to 17th and 18th century works, mostly portraits.