Berny's photos with the keyword: AON

left side: One Prudential Plaza, right side: AON Center scanned slide, Minolta X700

A bronze lion (1894) in front of the "Art Institute of Chicago" bites the AON building (see image before). - scanned slide, Minolta X700

AON Center in the background, behind the Chase Tower

Chicago 1986, AON Center seen from John Hancock Center, built 1970-1973, 83 floors, 346 m - scanned slide, Minolta X700 Architect: Edward Durell Stone The original marble cladding (here on this image) bowed under the temperature swings experienced in the Chicago climate. The cladding was 32mm thick Itallian Carrera Marble (similar to what Michaelangelo used), but 20 years after original construction it had severly deteriorated. The marble was replaced with 51mm thick Mt. Airy Granite at a cost of $80M between 1990 and 1992 (43000 individual 1.27m x 1.14m panels). The original construction cost in 1973 was a mere $120M.