The Bean in Chicago's Millennium Park is really Cloud Gate, 168 stainless-steel plates welded into one seamless, 110-ton mirror. Every day the park is open, a small crew hand-wipes its base to strip off the fingerprints and oils that would corrode the finish. Twice a year another crew scaffolds the whole sculpture overnight for a full wash and polish. The wipe-down crew is still out there, cloths in hand.
