This image shows a full crinoid fossil. Crinoids are the most common fossils in Indiana. Crinoids are from the Mississippian period in the Paleozoic era, 320 million years ago. My classmates came upon this at the Lake Monroe Spillway while looking for fossils.
Photo details: Camera Maker: SONY; Camera Model: DSC-W180; Focal Length: 6mm; Aperture: f/3.1; Exposure Time: 1/160 s; Metering Mode: Pattern; Exposure: 0 STEP; Light Source: Unknown; Flash Fired: No; Color Space: sRGB.