My grandparents found a rock at the beach that spontaneously combusted. what is it?
Later on their way back, the sun had rose and the rock was now fizzling , when they touched it with their sandal, it burst like a waterballoon of petrol and created a bright thick fire like an oil fire, as if the golf ball sized stone was filled with super heated napalm.
My grandparents kicked the small stone which had not melted, into the water and it made a huge explosion which intensified the flames, as if it were sodium.
My grandppa kept the stone after it had been burning in the shores wash line for an hour, and took it home. when he got home, he put it into a glass of water and it violently fizzled and sustained a flame momentarily.
i checked the so called stone, and it looked like a standard beach pepbble with a tiny bit of quartz attached.
What could it have been? that would have passivated in the water and not completely reacted until the inert skin was broken. my grandparents claim it was the sunlight that triggered the exothermic reaction.
Anyway, they say the flames werent blidingly bright which possibly rules out alkali metals, plus it was yello which rules out lithium ontop of the meals, as well as the fact that it had previously been under water.
does anyone know what it is? like i siad, it looks like standard smoothed beach rock now, its exterior was what burnt.