i was polishing the headlite rings from my 53 imperial, which has some pitting. i became curious as to why these pieces "pit" and what exactly is pitting. we all know what it looks like, but what is really the root cause. i would assume that age is a factor, but i also think it is more than that. the piece is made out of pot metal, and what is that made of and is that a contributing factor to pitting? i suppose the why's dont matter that much, but perhaps we can better prevernt our cars from getting future pitting if we know the answers. i know that there are many people on this site who can shed light on this subject. thanks, dennis 53 imperial[for sale]