The distinctive spire of the Chrysler Building, completed in 1930, is clad in a material called Enduro KA-2, a special German variant of non-rusting stainless steel. It was pretty cutting-edge for its day, and as the building has landmark status the material will likely never be replaced with anything different.
Which is not to say other, lesser-known skyscrapers will not see modern material upgrades. The Manhattan building known as 100 Park Avenue, one of the first steel and glass skyscrapers the city has known, is about to be re-shod with its own cutting-edge stuff: "Reynobond ACM with a Pewter, Kynar finish," by Alcoa Architectural Products.
The strong, rigid construction of Reynobond composite material consists of a compound core between two sheets of aluminum, brushed aluminum, zinc, stainless steel, copper or titanium. This creates a flat surface that virtually eliminates dimpling, buckling and oil canning.
Reynobond is easily routed, drilled, punched, cut, bent, curved and precisely formed via these and other fabrication techniques to achieve small-radius curves, reverse curves, angles and other shapes, to create dramatic and distinctive designs.
The light weight of Reynobond allows a wide variety of design options. Installation is quick and easy. For renovation work, cladding can often be installed with little or no alteration to existing structural elements.
Most importantly, Reynobond has a high recycled content, meaning it meets sustainable design standards; 100 Park Avenue will be New York City's first retrofitted building to receive LEED Silver certification.