While we road-tripped through your great Grand Canyon State last week, I worked with my daughter on her rocks project for school. With all that red rock and limestone all around us, she and I were charged with delving into the architecture of the Jefferson Memorial—a grand and important monument made solidly of Georgia marble and limestone and built in the image of the Pantheon of Rome. Things a third grader knows.

We also learned about the words inscribed in the dome and on the walls of this...