rock fulgurite Directory References Discover 9 of the World’s Deadliest Spiders 7 Famous Child Prodigies What’s the Difference Between Emoji and Emoticons? 7 of the World’s Deadliest Shipwrecks Nostradamus and His Prophecies Why Is It Called Black Friday? Which Religion Is the Oldest? Contents rock fulgurite mineral Learn about this topic in these articles:varieties of fulgurite In fulgurite>Rock fulgurites, the other variety, are thin, glassy crusts on rocks. They generally occur on mountain summits, as at Toluca, Mex., and Mt. Thielsen, Oregon. Read More