What architect Frank O. Gehry calls a "tempest in a teapot" is less likely a questioning of the attributes of titanium and more likely a testament to the value of good coordination among building team members. The 0.3-mm. titanium sheets used to clad the famed Guggenheim Museum  in Bilbao, Spain, as it turns out, are acquiring brownish stains after just three years installed in the humid, industrialized port city. Gehry accuses the general contractor of leaving silicon-based fireproofing on the roof and façade panels, causing the corrosion, and of ignoring his office's calls to clean the mess.
Owner's representative José Ignacio Vidarte, on the other hand, suspects that silica particles in Bilbao smog are a more likely culprit. The supplier of the metal sheets counters that the discoloration is the natural result of exposing titanium to air. The silica theory seems the most sound, however, and a nearby technical society, Fundación Inasmet of San Sebastián, Spain, will be applying a novel foam cleaning agent to make the appearance more uniform - at a modest cost.