A woman strolling along river shore in northern Germany mistook a chunk of white phosphorus from a World War II-era incendiary device for a semi-precious stone, police said Saturday.
The 41-year-old found the material in the wet sand while walking along the Elbe river bank near Hamburg and placed it in her pocket for safekeeping.
When the phosphorus chunk dried, it ignited itself and set fire to her jacket, police said, adding that the woman had not been injured in the incident.
A subsequent search of the beach for further phosphorous material did not yield any results.
White phosphorous burns at 1,300 degrees Celsius and creates fire that cannot be doused with water. Incandescent particles can produce extensive second and third degree burns.
