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.