Glass threads spun from volcano’s bubbly magma look like human hair

Most people associate ash and churning lava with volcanic activity, but volcanoes also produce formations that look unnervingly like human ponytails. – Graphic: The Star

Most people associate ash and churning lava with volcanic activity, but volcanoes also produce formations that look unnervingly like human ponytails.

Known as Pele’s hair, these thin strands of volcanic glass are named for Pele, a female figure in Hawaiian mythology associated with volcanism.

They’ve been reported raining down on yards and filling up rain gutters near volcanic regions in places like Hawaii and Iceland. According to new research by a team of scientists and glass artists, the delicate-looking structures may form when bubbly magma is stretched.

Pele’s hair can form when bits of lava are tossed up in the air and then stretched by jets of volcanic gases.

A team led by Janina Gillies, a geologist in New Zealand, and Ed Llewellin, a volcanologist in Britain, investigated how bundles of aligned strands of Pele’s hair might be created.

Early work showed that the presence of air bubbles was crucial to producing long strands.

Colin Rennie, a glass artist in Britain, helped the team prepare hockey-puck-size pieces of glass containing varying amounts of powdered calcium carbonate.

When they were heated to 1,093°C, the calcium carbonate decomposed and produced carbon dioxide gas. That created air bubbles in the pucks.

When air bubbles filled about three-quarters of the space, the pucks readily formed Pele’s hair-like threads when stretched.

But pucks with far fewer air bubbles formed one wide ribbon of glass. “The more bubbles there are, the more hairs that form,” Gillies said. That made sense because it was the glass between the bubbles that had stretched to form the hairs. — By Katherine Kornei/©2026 The New York Times Company