Phosphorus caused burning beach pebbles

A few weeks ago, we brought you news of a lady whose new collection of beach pebbles exploded in her pocket, sending her to the hospital and making a hazmat site of her home. Additional testing confirms that phosphorus is to blame.

The phosphorus on the smooth, greenish-orange rocks is likely manmade, said Kenneth Shea, an organic chemistry professor at the University of California, Irvine.
Phosphorus is found in oxidized form in rocks, but in its pure elemental form can burn when exposed to air. Phosphorous compounds are used in everything from flares to munitions to fertilizer.
"You can't go digging on the beach and find it," Shea said. "It's manmade, and it's pretty common."

 Burning rocks had elevated phosphate levels