Blade seen through sheath

Museum anthropologist Alex de Voogt wanted to examine the two blades of an Egyptian knife (inset) collected in the 1930s. Unfortunately, the sheath covering one of the blades presented problems. Its leather parts had shrunk, making it too tight to remove, and its lead strips were impenetrable to conventional X-rays. However, a more powerful solution was available: computed tomography, which can digitally remove the sheath. The payoff: a decorative pattern of Arabic letters is now visible on the blade.