A comparatively rare element occurring most abundantly in the mineral chromite. Atomic weight 52.5. Symbol Cr. When isolated it is a hard, brittle, grayish white metal, fusible with difficulty. Its chief commercial importance is for its compounds, as potassium chromate, lead chromate, etc., which are brilliantly colored and are used dyeing and calico printing. Called also chrome.
Compare?(See: heavy metals.)
Chromium (Cr) is a steel-gray, lustrous, hard, metallic element, and takes a high polish. The addition of a minimum of 12% chromium to steel makes stainless steel resist rust, or "stain-less" than other types of steel. The chromium in the steel combines with oxygen in the atmosphere to form a thin, invisible layer of chrome-containing oxide, called the "passive film." The film self-repairs in the presence of oxygen if the steel is damaged mechanically or chemically, and thus prevents corrosion from occurring.