Actually, I seem to have strayed out of English, but hey.
There I was, describing a petrifying well; and suddenly I needed all unexpectedly a word for someone or something who would eat the things thus petrified, a stone-muncher. And I thought, "lithophage - that should be the word!" and so I wrote it in. And then I googled it. Apparently it is the word - in French. Hey-ho.