Your eyes are about to die, just warning you. More than likely, the poem won't rhyme, but too bad. But yes, here we go...

Found in France and has a glow,

Period six is where you'll go.

Forever alone has how I'll be,

And I'm known for my Magnetic susceptibility.

I radiate some UV light,

flying sparks me give you a fright.

Five hundred grams could cause you to die,

and you can get me from montanazi(te sand)

Umm, I really don't know what happened with that last line, but anyway, there is your clue/poem thingy. Thank you for participating. ~ Blue