Triangle Stones?

[Grabe]

This stone was found along with another one in the fields. Both rocks are triangular in shape and both have some sort of mineral or something through the middle of the stones making it look like an oreo cookie.

[Hoss]

That look like a rock. Just a pebble from the river with two minerals the inner one is a bit softer and has broken down to make it appear like a groove. We call them sex rocks up here in CT.