Figure 6 Sample from the rear leg of the ewe, average surface thickness 0.9 microns. (Photo, Winterthur Museum.) The layers in this sample compare favorably with four bottom lavers of the standard (5.1-5.4). There is also a faint film on top of layer 6.4 that could be an oil polish corresponding to laver 5.6. The correlation between the layers on these samples supports the visual observation that the ewe is original.