The famed pigment which lends blueprints and Japanese woodblock prints their signature hue gives its name to the Piano tea towel in Blue de Prusse, lined in taut stripes resembling piano strings. Modern weaving techniques update linen made the traditional way in the cite de la toile, Armentières, the medieval city of fabric tucked into northern France. And like the city in which they are made, these essential kitchen accessories only get better with age — as they are not pre-washed, their hand will soften each time they are used.