For decades, a spectacular 1950s glass mosaic mural by the noted artist Max Spivak lay hidden. Last March, it was unexpectedly discovered during renovation work on the façade of 5 Bryant Park (111 West 40th Street.) In the spirit of Joan Miro, this colorful abstract mural depicts tools of garment designers and makers, which link it to the legacy of New York’s historic textile industry. David Dunlap, who wrote a compelling article in the New York Times about the uncovered mosaic, will be joined in conversation by Steve Miotto, the skilled craftsman hired for the restoration. Peter Rose of the Blackstone Group, owners of the building, will introduce them.