Hell Creek bone - Help!

[abctriplets]

So this was the largest bone we picked up on our great Out West trip. We had found it out on a ranch in Montana, as part of the Hell Creek formation. The bulk of the bone was a bit fragmentary, so our guide put a plaster wrap over the top of it. Turns out she just applied it directly to the bone, so I've spent the past few days scraping and scrubbing to get the plaster off.  I reglued the loose pieces as they came off, and assembled the fragments that were directly around the bone (during excavation) into 3 medium sized pieces (below). The smaller piece on the right was located *directly* under the large bone. In my dreams this would be a recognizable bone, and one I could make larger by attaching the other pieces to it. Here's the current state:

 

As you can see, it is interesting, and has shape. The socket in the large piece is what caught our attention initially. The smaller piece (right) that was found directly beneath the bone also has a socket. The bone structure in the large piece hints at shape (from the grain and the bits of outer bone that's left), and the small piece has a nice point opposite the socket. The bottom of the large piece (see below) is a nice smooth curve.

 

 

So...any thoughts? We were leaning towards some sort of hip bone, but feel there are a few other options that might fit as well. Or not at all. We're new to this. At this point, I thought if by chance I could figure out what the shape was supposed to be, that maybe I could better attempt the jigsaw puzzle.

 

[zekky]

Way too fragmented to tell in my opinion.

[abctriplets]

Yeah, but I thought perhaps experts here might be able to spitball an answer. I mean, what, aren't odds are that it'd be some chunk of triceratops or edmontosaurus? How many bones on a dino would have a curved socket for a condyle to fit in?

 

Knew it was a long shot though.