If it was dry aged at all the edges can become very dark and sometimes black. A local meat supplier lets hers age 25 days, not really dry aging just good practice, but I have seen it be black at the egdes. Is it sort of like jerky? If it is it would lead me to believe it was dry aged with a little to much air circulation. Was it cryovaced or in freezer paper?

I have see this. Not sure if it's coagulated blood or part of the aging process. Trim it off and call the rest dinner.

Well, I think it just might be the coagulated blood that
@friendlyoaks mentions and that combined with freezer burn. Smells fine you say so if you cut off the black, do you still have enough for dinner?

Oh feh! That's all. Except do you think it might be weirdly coagulated blood? Good luck on figuring this out. I will check back to see what wiser minds have to day about this. BTW, I used hanger steak just last week to make Amanda's sugar steak with bourbon. Oh so definitely not-feh.