Silurian Rock Core from Milwaukee deep tunnel. Purchased form Wisconsin Geological and Natural History Survey. Vuggy porosity is noticeable in this model. IN the photo you can see the red and blue lines marked on most rock cores to indicate which way is up. The rule is "Red on right". Scanned in Dr. Franek Hasiuk's GeoFabLab (Department of Geological and Atmospheric Sciences, Iowa State University). Scan Specifications: Scanned with the MakerBot Digitizer Desktop 3D Scanner set on "Medium".