411 on a couple rocks or fossils???

[Swims with Beaver]

I went hunting a couple corn fields for arrowheads and ran into these a couple weeks apart. The second rock sparkles a little bit in the right light. In the little divot hole there looks like there's crystals in it. Any info would be much appreciated. Thanx.

 

[Harry Pristis]

It appears you have stream-abraded colonial corals. Sometimes these are filled in solid, sometimes not. Here's an example of one that is not filled in:

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[Tuberale]

First looks like a portion of a tooth: has dentine still on portion, slightly porous bone on the rest. Similar to coral, but not an exact match, I think.

The second stone does look like coral to my eye.