24 janv. 1884 - Carborundum is a very hard mixture consisting primarily of silicon carbide; it is used as an abrasive and, in powdered form, in a method of engraving invented by Henri Goetz. He used it to get a dotted effect by sprinkling it over a metal plate which was then pulled through a press, which got the grains to push into the metal.
Ajouté au bande de temps:
Date:
24 janv. 1884
Maintenaint
~ Il y a 141 ans