Out of Place Geodes?

When you're a geology professor, people often bring you things to identify. Usually, it's something easy to figure out (especially if it's local) and sometimes you have to disappoint them (supposed meteorites that turn out to be slag, for example). Occasionally, however, you get something truly odd.

A faculty colleague recently showed me some rocks that were dug up by her kid and friends at the base of a tree in a suburban area near Cantine Field in Saugerties, NY. A half-dozen or so spherical rocks several inches in diameter. 

At first they almost looked like cement, rather than rock, but after cracking a few open, we were surprised to find they were geodes. Even more surprising, they were all slightly different.

The one on the left took several swings of a heavy sledge to bust open and you can see there's a vein of chalcedony/chert running through the middle. The middle one had nice quartz crystals in the center, and the right one had well-formed calcite crystals!

The one on the left was even more odd. It had some white crystals (shown) that fizzed with hydrochloric acid (which would normally indicate calcite) but then when I washed the rock, they started to get soft and dissolve (which calcite does not do). I'm not sure what they are.

So, how did a pile of geodes end up in Saugerties? I have no idea. The bedrock in the nearby area is the Devonian Onondaga Limestone. I've never seen natural geodes in the area. My only guess is that they were once dumped there by someone. Where did the geodes originally come from? No idea. It's a mystery.

Do any readers recognize where they might be originally from or how they might have gotten there? Let me know!