Does anyone know what this grill is made of and can it be welded??? Feels to heavy to be aluminum but I'm guessing it's sum cast iron. I want to put it back on my car. Would anyone recommend rigging sum type of plate to attach them back to the car

 

That looks to be a Supreme grille, which is made of a cast metal (pot metal or similar). You might be able to repair it with an epoxy such as JB Weld.

 

It is pot metal, which is die cast zinc and not easily welded. There are specialty vendors who can repair and rechrome pot metal parts. It is not inexpensive.