I figure it is some "broadspear" and I did find similar examples to the Susquehanna Broadspear. I think you're right. I don't think the middle one is poplar island (of which I've found a few.) Looks more like a lackawaxen point which seems to be common around Philly? Now as far as the lithic goes on the broadspear -- I have no idea. I tend to call just about all flat black stuff argillite simply because I don't know the difference, but it very well can be basalt. Not sure... I just can't believe it's not broken. It's super thin and found on a very rocky beach.