stupid question: Distributor gears?

I ordered an msd Steel gear from summit. It arrived and the package was already open, no big deal, may have been something someone returned.

Is there any way to verify that what I have is steel and not iron? I would like to make sure it's not something some guy swapped gears with and sent back.

So, the difference between steel and iron? Any easy way to tell other than finding the density which I can't do sine I don't have an accurate scale.
 
No, More than likely it is the correct gear, It would just be nice to be 100% positive before I install it. It has never been used or installed (not drilled through) but there is still a chance some guy my had an extra gear laying around and decided he could score the free gear that he needed by buying one and returning his. I doubt it though, in the whole that is drilled it does appear to be steel (looks like steel) but then again I don't really know how that looks compared to raw iron.