This photo made me chuckle today. In Pompeii, the impressions made when the lava hardened over the dead bodies of its inhabitants created an accidental mold. (See my previous post: Plaster Cast of a Man Who Died in Pompeii, 79AD)
Here are the results when one of those molds is used repeatedly. In this case, it is the mold of a dog with a chain collar that died in the eruption of Vesuvius in 79AD. The casts were made by artist Allan McCollum in 1991 in collaboration with the Museo Vesuviano, the Pompei Tourist Board, and Studio Trisorio in Naples. [Source: Allan McCollum Album]
[Correction]: An earlier version of this post stated that only the photo was taken by Allan McCollum, instead of both the photos and the casts.