This is a sample of columnular basalt in the Field Museum in Chicago:
The famous place I’ve heard of this formation is the Giant’s Causeway, a cliff on the northern coast of Ireland. There’s a geological explanation and a legendary one, a tale I enjoy because the hero actually dodges the issue and defeats the villain with a trick instead of a fight. In Rite of Return the hero and heroine end up at Giant’s Causeway at a moment when the heroine is questioning why she’s in the country. It was a scene that took me a long time to write, and I did a lot of staring at photos of columnular basalt while I was trying to do it.
So we’re in Chicago for spring break hitting all the museums and having a fabulous time. It’s one of those trips where I have to keep stopping to take notes for later; I want to sleep twelve hours a night to absorb all I’ve seen during the day. We went to the Field Museum to see mammoths and spent a long time in the Egypt exhibit. Then I turned a corner and saw the basalt. On one side was a display about a 1938 meteorite that fell through a guy’s garage and car before denting to a halt on the muffler. On the other was the geology of the Chicago area, which as far as I can tell has not a whiff of columnular basalt.
But here were these pieces, looking just like the photos. They’re about 18 inches across. And I have more writing to do.