Hello Everyone!
Found this plate at a Maryland fossil site of Mid-Silurian age in the McKenzie Formation/Rochester shale. First thought was plant but plant fossils in north America first show up in the late Silurian. microscope pictures don't show any cellular structure, though early plants would not have xylem. When rubbed a black dust comes of it, but not super crumbly like low grade coal. Could be hematized worm burrow? Not the typical type of preservation here. The environment is shallow water, with the main fossils being ostracods, brachiopods, tentaculitids, and some worm burrows that look quite different from this. Next to it is a silvery fossil (typical preservation, don't know what mineral it is) with many little holes in it. What say you?
First up, micro shots