Do You Know Why Two of the Rocks Catch Fire?

A 43 year old woman in Orange County, California, suffered third degree burns to her leg and hand. Local health officials say that two of the rocks contain a phosphorus substance but there still is no definitive explanation as to why they might have caught on fire. Dr. McLaughlin feels like he's left his only quote left with a conclusion that ferriti's death fits into the category of spontaneous human combustion.