Ornamental ironwork is an unobtrusive art; many of us go through life without being aware of it at all. But there is something so impressive about the way a rod of solid iron can be heated and hammered and worked into delicate tendrils and spirals, each slightly different from its neighbor, that once you’re introduced to the craft, you stay aware of it. You might even begin to search it out. An exhibition on view at the National Cathedral in Washington, D.C., through the end of October salutes America’s acknowledged genius in the field, Samuel Yellin. The exhibit was mounted with the help of his granddaughter, Clare Yellin, who carries on the family business in Philadelphia.

Yellin himself called iron the “salt and pepper of architecture”—not central, perhaps, but indispensable nonetheless. Born in Poland, he was already a master metalworker when he arrived in this country in 1906, at the age of twenty-one. “My grandfather was a collector, an archivist, a librarian, a blacksmith par excellence ” Clare Yellin explains. “For inspiration he collected fine examples of medieval metalwork. He loved giving lectures and teaching about craft. He wanted to make craft in this country something to be proud of. And he was such a good designer that after a while architects would leave sections of their drawings blank and write ‘Design by Yellin.’”

From 1909 to 1940, an era that coincided with America’s fascination with revival styles, his shop in Philadelphia turned out the grilles and gates that added savor to the nation’s Gothic- and Renaissance-inspired churches, museums, banks, colleges, and estates. During the 1920s the firm had so many orders that it employed more than two hundred blacksmiths, but there was never any doubt who was in charge. A set of plans on display in the cathedral is rubber-stamped “See Mr. Yellin before starting work.”

Yellin won commissions in thirty-eight states, and much of what he produced is still around. Yale University has ten of his gates; the National Cathedral has five; in New York City you can see his work at the Cloisters, the Morgan Library, and the Federal Reserve Bank on Wall Street. Although he called himself a traditionalist, his work has an exuberance that makes it seem modern. Yellin was convinced there was no point in copying old designs. “The result is never a copy—no such thing exists. It is either better or worse than the original.” Yellin is better.