For three years and counting, Kim and I have spent nearly every warm or warmish Sunday in her Minneapolis backyard. It started with a mad impulse. I brought home a rock of indigo from Oaxaca and tried to imagine which friend of mine would be crazy enough to work with me to coax from it the beautiful hue of cobalt blue treasured the world over.

I knew it would require chemistry skills and superb aesthetics and an intrepid patience—if there is such a thing. Kim, who combines both the brain of a scientist with the technical skills of a fiber artist, was my go-to. And we’ve been at it ever since.