Could use some help

[SouthTexasFinds]

Always assumed these were fossilized oyster shells, but not so sure anymore. I keep finding thicker, and larger pieces. Could use any help. Found the first one with an Native American tool, and the second with a arrowhead laying against it. The first almost appears worked to a blade. And ideas or input greatly appreciated. Thanks for looking


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The last one is the first full one I have found. I had tried to get any mud/dirt out of it but it has mostly all turned into sand/mud stone.


I also found a few chucks of fossilized sediment with these shells attached and included if that would help at all

 

[Harry Pristis]

They certainly appear to be oysters.

 

[SouthTexasFinds]

Agreed they look like oysters, only much bigger. If I had to guess the big broken one must have been at LEAST 10in wide/long. I have never seen an oyster close to that big. Although I guess they could have been that big way back when?

 

[mamabear]

I have found oysters that big in the Hood Canal, WA. Monsters! Best for oyster stew.

 

[old digger]

Nice Find! I have found similar Mussel/Oyster fossil shells here in Montana near the Musselshell River, (From which it gets it's name). When you find them they appear to matted/sandwiched together in thick layers. It is quite possible that very large ones did exist.