Not much to show with this specimen. It's a single fossil of an inarticulate brachiopod called Orbiculoidea truncata. I found it along the cliffs that line Lake Erie near 18 Mile Creek. It likely came down from the Windom shale as I found it in an area that had the Wanakah shale covered by talus from the overlying rock.
The Wanakah shale is part of the Ludlowville formation which is Devonian (Givetian stage) in age.