Carbon Nanotubes
This collection of images are engineered carbon nanotubes. They most certainly are fibers and are highly crystalline and should be compared with the fibers elsewhere in this library. The lines along the length of the tube demark layers of graphite (a form of crystalline carbon) the distance between each is 0.34 nm. You will notice that some of these nanotubes are starting to "fall apart" at their periphery.