Chromium is a chemical element with symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-grey, lustrous, hard and brittle metal which takes a high polish, resists tarnishing, and has a high melting point.
C 3225 (OTTO) Chromium foil, thickness 0.5 mm, 99.99% Cas 7440-47-3 - used not only as a component of paints, but in tanning salts as well.