*Correction (3/17/15): The periodic table has been updated to include thallium.
Half a century ago only a handful of materials were in widespread use for consumer and industrial products—wood, iron and brick, to name a few of the most prominent ones. Today a single computer chip contains more than 60 elements, ranging from tungsten to ytterbium. Contemporary technology's reliance on such diverse resources, particularly metals, piqued the interest of Thomas Graedel, an environmental scientist at Yale University. With increasing demand for these elements, are replacements available if a shortage occurs?
In most cases, no. In fact, strong substitutes exist for none of the examined 62 metals or metalloids on the periodic table in all their uses, Graedel and his colleagues found after a comprehensive analysis of the elements' properties, life cycles and applications. And inadequate or nonexistent alternatives plagued a dozen metals when it came to their major uses. Replacements in these cases invariably would lead to degraded performance.
There may be a silver lining to situational scarcities, however, Graedel says. They should inspire engineers to design completely novel, transformative materials.