Deepwater Pottery: Problems and Potentials

Figure 1. Soft mud from within an 8th Century BC earthenware cooking pot retrieved from a depth of 500 meters in the Eastern Mediteranean. The mud shows wood grain pseudomorphing formed by the incorporation of sediment into decaying timbers. Note the color change in the mud. It marks the boundary of reducing conditions and may also indicate the surface of original wood.

Figure 2. Close-up of Figure 1. Figs. 1 and 2 are meant to show how biodeterioration in the low energy deposition environment of deepwater includes no dispersal of the degraded organics. This leaves behind very ephemeral pseudomorphs of the original structures. Flotation showed no actual woody material was present. This surface became visible only after carefully misting the humic sediment with water.

Figure 3. The same vessel photographed after initial cleaning. Note the old vertical rim crack to the left.

Figure 4. Same pot after desalination and careful drying showing the extensive cracking due to shrinkage stress. Such cracking is opportunistic- taking advantage of any weakness in the pot like the old rim crack. But it happens more often on the exposed surfaces than the submerged. Currently it appears that the cracking is due to stresses developing between the exposed and submerged sides of pottery.

The artifact in the above photographs was conserved as part of an expedition to the Eastern Mediterranean Sea. The expedition team included archaeologists from the Leon Levy Expedition at Ashkelon, Israel under the direction of Dr. Lawrence Stager of Harvard University. Dr. Ballard, Project Leader for the Expedition, was joined by oceanographers and engineers from Woods Hole Oceanographic Institution, Massachusetts Institute of Technology, and Johns Hopkins University.